U.S. patent application number 14/813269 was filed with the patent office on 2017-02-02 for real-time analysis for dynamic storage.
The applicant listed for this patent is NetApp Inc.. Invention is credited to Nandakumar Ravindranath Allu, Sachithananthan Kesavan, Rajesh Nagarajan.
Application Number | 20170031600 14/813269 |
Document ID | / |
Family ID | 57882508 |
Filed Date | 2017-02-02 |
United States Patent
Application |
20170031600 |
Kind Code |
A1 |
Kesavan; Sachithananthan ;
et al. |
February 2, 2017 |
REAL-TIME ANALYSIS FOR DYNAMIC STORAGE
Abstract
One or more techniques and/or systems are provided for
dynamically provisioning logical storage pools of storage devices
for applications. For example, a logical storage pool, of one or
more storage devices, may be constructed based upon a service level
agreement for an application (e.g., an acceptable latency, an
expected throughput, etc.). Real-time performance statistics of the
logical storage pool may be collected and evaluated against the
service level agreement to determine whether a storage device does
not satisfy the service level agreement. For example, a latency of
a storage device within the logical storage pool may increase
overtime as log files and/or other data of the application
increase. Accordingly, a new logical storage pool may be
automatically and dynamically defined and provisioned for the
application to replace the logical storage pool. The new logical
storage pool may comprise storage devices expected to satisfy the
storage level agreement.
Inventors: |
Kesavan; Sachithananthan;
(Karnataka, IN) ; Nagarajan; Rajesh; (Tamil Nadu,
IN) ; Allu; Nandakumar Ravindranath; (Tamil Nadu,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NetApp Inc. |
Sunnyvale |
CA |
US |
|
|
Family ID: |
57882508 |
Appl. No.: |
14/813269 |
Filed: |
July 30, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 3/0665 20130101;
G06F 3/067 20130101; G06F 2212/154 20130101; G06F 3/0605 20130101;
G06F 2212/217 20130101; G06F 3/0631 20130101; G06F 2212/263
20130101 |
International
Class: |
G06F 3/06 20060101
G06F003/06; G06F 12/02 20060101 G06F012/02 |
Claims
1. A method for dynamically provisioning a logical storage pool of
storage devices for an application, comprising: identifying a
service level agreement (SLA) for an application; evaluating a
storage environment to identify a pool of storage devices available
for hosting data of the application; constructing a logical storage
pool comprising one or more storage devices selected from the pool
of storage devices based upon the SLA; and provisioning the logical
storage pool for the application.
2. The method of claim 1, comprising: collecting real-time
performance statistics associated with the one or more storage
devices, within the logical storage pool, hosting the data the
application.
3. The method of claim 2, comprising: comparing the real-time
performance statistics with the SLA to identify a storage device
that does not satisfy the SLA; defining a new logical storage pool
comprising storage devices that satisfy the SLA and a replacement
storage device used to replace the storage device that does not
satisfy the SLA; migrating data from the storage device that does
not satisfy the SLA to the replacement storage device; and
provisioning the new logical storage pool for the application.
4. The method of claim 1, comprising: constructing a set of logical
storage pools for the application based upon the SLA; and
provisioning the set of logical storage pools for the
application.
5. The method of claim 4, comprising: collecting real-time
performance statistics associated with the set of logical storage
pools hosting the data of the application; determining that a first
logical storage pool of the set of logical storage pools does not
satisfy the SLA based upon the real-time performance statistics;
and migrating data from the first logical storage pool to a second
logical storage pool that will satisfy the SLA.
6. The method of claim 5, the migrating data comprising:
determining that the second logical storage pool will satisfy the
SLA based upon at least one of cost, disk size, latency, or
throughput.
7. The method of claim 3, comprising: releasing the storage device,
that does not satisfy the SLA, into an available storage pool of
the storage environment.
8. The method of claim 2, comprising: comparing the real-time
performance statistics with the SLA to identify a storage device
that satisfies the SLA; identifying a second storage device that
will satisfy the SLA; responsive to a cost of the storage device
exceeding a second cost of the second storage device: defining a
new logical storage pool comprising storage devices that satisfy
the SLA and the second storage device used to replace the storage
device; migrating data from the storage device to the second
storage device; and provisioning the new logical storage pool for
the application.
9. The method of claim 2, comprising: identifying an updated SLA
for the application; comparing the real-time performance statistics
with the updated SLA to identify a storage device that does not
satisfy the updated SLA; defining a new logical storage pool
comprising storage devices that satisfy the updated SLA and a
replacement storage device used to replace the storage device that
does not satisfy the updated SLA; migrating data from the storage
device that does not satisfy the updated SLA to the replacement
storage device; and provisioning the new logical storage pool for
the application.
10. The method of claim 3, the migrating and the provisioning
comprising: providing a suggestion of the new logical storage pool
to an administrator; and responsive to receiving a new provision
command from the administrator in response to the suggestion,
performing the migrating and the provisioning.
11. The method of claim 3, the migrating and the provisioning
comprising: responsive to the storage device not satisfying the
SLA, automatically performing the migrating and the provisioning
during real-time operation of the storage environment.
12. The method of claim 1, the provisioning the logical storage
pool comprising: creating at least one of a volume or a logical
unit number (LUN) across at least one storage device of the logical
storage pool for use by the application.
13. The method of claim 1, the pool of storage devices comprising
at least one of cloud storage, a solid state drive (SSD), virtual
storage, a logical unit number (LUN) array, a tape drive, a serial
attached small computer system interface (SAS), or a serial
advanced technology attachment (SATA).
14. The method of claim 4, the set of logical storage pools
comprising a first logical storage pool, comprising a first storage
device and a second storage device, and the second logical storage
pool comprising a third storage device and a fourth storage
device.
15. The method of claim 14, the first storage device comprising a
first storage device type different than a second storage device
type of the second storage device, the third storage device
comprising a third storage device type different than at least one
of the first storage device type or the second storage device type,
and the fourth storage device comprising a fourth storage device
type different than at least one of the first storage device type,
the second storage device type, or the third storage device
type.
16. A system for dynamically provisioning a logical storage pool of
storage devices for an application, comprising: a processor; and a
memory containing instructions which when executed by the processor
implement at least some of: a dynamic storage provisioning
component configured to: identify a service level agreement (SLA)
for an application; evaluate a storage environment to identify a
pool of storage devices available for hosting data of the
application; construct a logical storage pool comprising one or
more storage devices selected from the pool of storage devices
based upon the SLA; and provision the logical storage pool for the
application.
17. The system of claim 16, the dynamic storage provisioning
component configured to: collect real-time performance statistics
associated with the one or more storage devices, within the logical
storage pool, hosting the data the application.
18. The system of claim 17, the dynamic storage provisioning
component configured to: compare the real-time performance
statistics with the SLA to identify a storage device that does not
satisfy the SLA; define a new logical storage pool comprising
storage devices that satisfy the SLA and a replacement storage
device used to replace the storage device that does not satisfy the
SLA; migrate data from the storage device that does not satisfy the
SLA to the replacement storage device; and provision the new
logical storage pool for the application.
19. The system of claim 17, the dynamic storage provisioning
component configured to: identify an updated SLA for the
application; compare the real-time performance statistics with the
updated SLA to identify a storage device that does not satisfy the
updated SLA; define a new logical storage pool comprising storage
devices that satisfy the updated SLA and a replacement storage
device used to replace the storage device that does not satisfy the
updated SLA; migrate data from the storage device that does not
satisfy the updated SLA to the replacement storage device; and
provision the new logical storage pool for the application.
20. A computer readable medium comprising instructions which when
executed perform a method for dynamically provisioning a logical
storage pool of storage devices for an application, comprising:
identifying a service level agreement (SLA) for an application;
evaluating a storage environment to identify a pool of storage
devices available for hosting data of the application; constructing
a set of logical storage pools for the application based upon the
SLA; provisioning the set of logical storage pools for the
application; collecting real-time performance statistics associated
with the set of logical storage pools hosting the data of the
application; determining that a first logical storage pool of the
set of logical storage pools does not satisfy the SLA based upon
the real-time performance statistics; and migrating data from the
first logical storage pool to a second logical storage pool that
will satisfy the SLA.
Description
BACKGROUND
[0001] Many computing environments, such as datacenters or other
storage environments, may be configured to provide various clients
with access to computing resources, such as data storage. A storage
administrator may provision one or more storage devices for use by
a client, such as to store data of an application. For example, a
database application may store a database within a volume of a
storage device provisioned by the storage administrator to a client
hosting the database application. Various types of storage devices
may be available for the storage administrator to provision, such
as cloud storage, a solid state drive (SSD), virtual storage, a
logical unit number (LUN) array, a tape drive, a serial attached
small computer system interface (SAS) storage device, a serial
advanced technology attachment (SATA) storage device, etc. The
storage administrator may manually select and configure the one or
more storage devices for provisioning based upon theoretical data
and personal experience regarding what storage devices may satisfy
a service level agreement (SLA) such as a desired throughput, data
loss protection, an acceptable latency (e.g., a data retrieval
latency of database data from the storage device), and/or other
performance characteristics associated with the database
application. Unfortunately, manual configuration may be cumbersome
and imprecise, which may result in inefficient allocation and
utilization of resources of a storage environment.
[0002] Overtime, the application may experience degraded
performance from the provisioned storage devices of the storage
environment due to increases in data being stored and managed,
increased log data, increased workloads, and/or management of other
values and information that may decrease performance. The storage
administrator may have to manually create a new group of storage
devices to provision for the application. The storage administrator
may take the application offline, migrate data to the new group of
storage devices, and provision the new group of storage devices for
use by the application. Manual configuration and/or reconfiguration
of storage devices for provisioning to applications may result in
reduced performance of applications, inefficient utilization of
computing resources of a storage environment, and cumbersome and
imprecise manual selection and configuration efforts by storage
administrators.
DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is a component block diagram illustrating an example
clustered network in accordance with one or more of the provisions
set forth herein.
[0004] FIG. 2 is a component block diagram illustrating an example
data storage system in accordance with one or more of the
provisions set forth herein.
[0005] FIG. 3 is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool of storage devices for an application.
[0006] FIG. 4A is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a pool of storage devices are identified.
[0007] FIG. 4B is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a first logical storage pool is provisioned.
[0008] FIG. 4C is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a second logical storage pool is dynamically
provisioned.
[0009] FIG. 4D is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a third logical storage pool is dynamically
provisioned.
[0010] FIG. 4E is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a fourth logical storage pool is dynamically
provisioned.
[0011] FIG. 5A is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a pool of storage devices are identified.
[0012] FIG. 5B is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a first logical storage pool, a second logical storage
pool, and a third logical storage pool are provisioned.
[0013] FIG. 5C is a component block diagram illustrating an
exemplary system for dynamically provisioning a logical storage
pool, where a third logical storage pool is released.
[0014] FIG. 6 is an example of a computer readable medium in
accordance with one or more of the provisions set forth herein.
DETAILED DESCRIPTION
[0015] Some examples of the claimed subject matter are now
described with reference to the drawings, where like reference
numerals are generally used to refer to like elements throughout.
In the following description, for purposes of explanation, numerous
specific details are set forth in order to provide an understanding
of the claimed subject matter. It may be evident, however, that the
claimed subject matter may be practiced without these specific
details. Nothing in this detailed description is admitted as prior
art.
[0016] One or more systems and/or techniques for dynamically
provisioning a logical storage pool of storage devices for an
application are provided. A logical storage pool, of one or more
storage device types that are automatically selected based upon a
service level agreement for an application, may be dynamically
constructed and provisioned for the application, which may reduce
error and/or inefficiencies otherwise introduced by manual
configuration and provisioning by a storage administrator.
Real-time performance statistics of the provisioned storage devices
hosting data of the application may be collected, and compared to
the service level agreement. If a storage device does not satisfy
the service level agreement, a replacement storage device type may
be automatically selected to dynamically replace the storage device
so that the service level agreement may be satisfied, which may
increase performance of the application in a dynamic and automated
manner as opposed to waiting on the storage administrator to
manually configure a new storage pool.
[0017] To provide context for dynamically provisioning a logical
storage pool of storage devices for an application, FIG. 1
illustrates an embodiment of a clustered network environment or a
network storage environment 100. It may be appreciated, however,
that the techniques, etc. described herein may be implemented
within the clustered network environment 100, a non-cluster network
environment, and/or a variety of other computing environments, such
as a desktop computing environment. That is, the instant
disclosure, including the scope of the appended claims, is not
meant to be limited to the examples provided herein. It will be
appreciated that where the same or similar components, elements,
features, items, modules, etc. are illustrated in later figures but
were previously discussed with regard to prior figures, that a
similar (e.g., redundant) discussion of the same may be omitted
when describing the subsequent figures (e.g., for purposes of
simplicity and ease of understanding).
[0018] FIG. 1 is a block diagram illustrating an example clustered
network environment 100 that may implement at least some
embodiments of the techniques and/or systems described herein. The
example environment 100 comprises data storage systems or storage
sites 102 and 104 that are coupled over a cluster fabric 106, such
as a computing network embodied as a private Infiniband, Fibre
Channel (FC), or Ethernet network facilitating communication
between the storage systems 102 and 104 (and one or more modules,
component, etc. therein, such as, nodes 116 and 118, for example).
It will be appreciated that while two data storage systems 102 and
104 and two nodes 116 and 118 are illustrated in FIG. 1, that any
suitable number of such components is contemplated. In an example,
nodes 116, 118 comprise storage controllers (e.g., node 116 may
comprise a primary or local storage controller and node 118 may
comprise a secondary or remote storage controller) that provide
client devices, such as host devices 108, 110, with access to data
stored within data storage devices 128, 130. Similarly, unless
specifically provided otherwise herein, the same is true for other
modules, elements, features, items, etc. referenced herein and/or
illustrated in the accompanying drawings. That is, a particular
number of components, modules, elements, features, items, etc.
disclosed herein is not meant to be interpreted in a limiting
manner.
[0019] It will be further appreciated that clustered networks are
not limited to any particular geographic areas and can be clustered
locally and/or remotely. Thus, in one embodiment a clustered
network can be distributed over a plurality of storage systems
and/or nodes located in a plurality of geographic locations; while
in another embodiment a clustered network can include data storage
systems (e.g., 102, 104) residing in a same geographic location
(e.g., in a single onsite rack of data storage devices).
[0020] In the illustrated example, one or more host devices 108,
110 which may comprise, for example, client devices, personal
computers (PCs), computing devices used for storage (e.g., storage
servers), and other computers or peripheral devices (e.g.,
printers), are coupled to the respective data storage systems 102,
104 by storage network connections 112, 114. Network connection may
comprise a local area network (LAN) or wide area network (WAN), for
example, that utilizes Network Attached Storage (NAS) protocols,
such as a Common Internet File System (CIFS) protocol or a Network
File System (NFS) protocol to exchange data packets.
Illustratively, the host devices 108, 110 may be general-purpose
computers running applications, and may interact with the data
storage systems 102, 104 using a client/server model for exchange
of information. That is, the host device may request data from the
data storage system (e.g., data on a storage device managed by a
network storage control configured to process I/O commands issued
by the host device for the storage device), and the data storage
system may return results of the request to the host device via one
or more network connections 112, 114.
[0021] The nodes 116, 118 on clustered data storage systems 102,
104 can comprise network or host nodes that are interconnected as a
cluster to provide data storage and management services, such as to
an enterprise having remote locations, cloud storage (e.g., a
storage endpoint may be stored within a data cloud), etc., for
example. Such a node in a data storage and management network
cluster environment 100 can be a device attached to the network as
a connection point, redistribution point or communication endpoint,
for example. A node may be capable of sending, receiving, and/or
forwarding information over a network communications channel, and
could comprise any device that meets any or all of these criteria.
One example of a node may be a data storage and management server
attached to a network, where the server can comprise a general
purpose computer or a computing device particularly configured to
operate as a server in a data storage and management system.
[0022] In an example, a first cluster of nodes such as the nodes
116, 118 (e.g., a first set of storage controllers configured to
provide access to a first storage aggregate comprising a first
logical grouping of one or more storage devices) may be located on
a first storage site. A second cluster of nodes, not illustrated,
may be located at a second storage site (e.g., a second set of
storage controllers configured to provide access to a second
storage aggregate comprising a second logical grouping of one or
more storage devices). The first cluster of nodes and the second
cluster of nodes may be configured according to a disaster recovery
configuration where a surviving cluster of nodes provides
switchover access to storage devices of a disaster cluster of nodes
in the event a disaster occurs at a disaster storage site
comprising the disaster cluster of nodes (e.g., the first cluster
of nodes provides client devices with switchover data access to
storage devices of the second storage aggregate in the event a
disaster occurs at the second storage site).
[0023] As illustrated in the exemplary environment 100, nodes 116,
118 can comprise various functional components that coordinate to
provide distributed storage architecture for the cluster. For
example, the nodes can comprise a network module 120, 122 and a
data module 124, 126. Network modules 120, 122 can be configured to
allow the nodes 116, 118 (e.g., network storage controllers) to
connect with host devices 108, 110 over the network connections
112, 114, for example, allowing the host devices 108, 110 to access
data stored in the distributed storage system. Further, the network
modules 120, 122 can provide connections with one or more other
components through the cluster fabric 106. For example, in FIG. 1,
a first network module 120 of first node 116 can access a second
data storage device 130 by sending a request through a second data
module 126 of a second node 118.
[0024] Data modules 124, 126 can be configured to connect one or
more data storage devices 128, 130, such as disks or arrays of
disks, flash memory, or some other form of data storage, to the
nodes 116, 118. The nodes 116, 118 can be interconnected by the
cluster fabric 106, for example, allowing respective nodes in the
cluster to access data on data storage devices 128, 130 connected
to different nodes in the cluster. Often, data modules 124, 126
communicate with the data storage devices 128, 130 according to a
storage area network (SAN) protocol, such as Small Computer System
Interface (SCSI) or Fiber Channel Protocol (FCP), for example.
Thus, as seen from an operating system on a node 116, 118, the data
storage devices 128, 130 can appear as locally attached to the
operating system. In this manner, different nodes 116, 118, etc.
may access data blocks through the operating system, rather than
expressly requesting abstract files.
[0025] It should be appreciated that, while the example embodiment
100 illustrates an equal number of network and data modules, other
embodiments may comprise a differing number of these modules. For
example, there may be a plurality of network and data modules
interconnected in a cluster that does not have a one-to-one
correspondence between the network and data modules. That is,
different nodes can have a different number of network and data
modules, and the same node can have a different number of network
modules than data modules.
[0026] Further, a host device 108, 110 can be networked with the
nodes 116, 118 in the cluster, over the networking connections 112,
114. As an example, respective host devices 108, 110 that are
networked to a cluster may request services (e.g., exchanging of
information in the form of data packets) of a node 116, 118 in the
cluster, and the node 116, 118 can return results of the requested
services to the host devices 108, 110. In one embodiment, the host
devices 108, 110 can exchange information with the network modules
120, 122 residing in the nodes (e.g., network hosts) 116, 118 in
the data storage systems 102, 104.
[0027] In one embodiment, the data storage devices 128, 130
comprise volumes 132, which is an implementation of storage of
information onto disk drives or disk arrays or other storage (e.g.,
flash) as a file-system for data, for example. Volumes can span a
portion of a disk, a collection of disks, or portions of disks, for
example, and typically define an overall logical arrangement of
file storage on disk space in the storage system. In one embodiment
a volume can comprise stored data as one or more files that reside
in a hierarchical directory structure within the volume.
[0028] Volumes are typically configured in formats that may be
associated with particular storage systems, and respective volume
formats typically comprise features that provide functionality to
the volumes, such as providing an ability for volumes to form
clusters. For example, where a first storage system may utilize a
first format for their volumes, a second storage system may utilize
a second format for their volumes.
[0029] In the example environment 100, the host devices 108, 110
can utilize the data storage systems 102, 104 to store and retrieve
data from the volumes 132. In this embodiment, for example, the
host device 108 can send data packets to the network module 120 in
the node 116 within data storage system 102. The node 116 can
forward the data to the data storage device 128 using the data
module 124, where the data storage device 128 comprises volume
132A. In this way, in this example, the host device can access the
storage volume 132A, to store and/or retrieve data, using the data
storage system 102 connected by the network connection 112.
Further, in this embodiment, the host device 110 can exchange data
with the network module 122 in the host 118 within the data storage
system 104 (e.g., which may be remote from the data storage system
102). The host 118 can forward the data to the data storage device
130 using the data module 126, thereby accessing volume 132B
associated with the data storage device 130.
[0030] It may be appreciated that dynamic provisioning of a logical
storage pool may be implemented within the clustered network
environment 100. For example, a dynamic storage provisioning
component may be implemented for the node 116 and/or the node 118.
The dynamic storage provisioning component may be configured to
automatically and dynamically provision and/or reprovision storage,
such as volume 132A of data storage device 128 and/or volume 132B
of data storage device 130, for use by an application hosted on
host device 108 and/or host device 110.
[0031] FIG. 2 is an illustrative example of a data storage system
200 (e.g., 102, 104 in FIG. 1), providing further detail of an
embodiment of components that may implement one or more of the
techniques and/or systems described herein. The example data
storage system 200 comprises a node 202 (e.g., host nodes 116, 118
in FIG. 1), and a data storage device 234 (e.g., data storage
devices 128, 130 in FIG. 1). The node 202 may be a general purpose
computer, for example, or some other computing device particularly
configured to operate as a storage server. A host device 205 (e.g.,
108, 110 in FIG. 1) can be connected to the node 202 over a network
216, for example, to provides access to files and/or other data
stored on the data storage device 234. In an example, the node 202
comprises a storage controller that provides client devices, such
as the host device 205, with access to data stored within data
storage device 234.
[0032] The data storage device 234 can comprise mass storage
devices, such as disks 224, 226, 228 of a disk array 218, 220, 222.
It will be appreciated that the techniques and systems, described
herein, are not limited by the example embodiment. For example,
disks 224, 226, 228 may comprise any type of mass storage devices,
including but not limited to magnetic disk drives, flash memory,
and any other similar media adapted to store information,
including, for example, data (D) and/or parity (P) information.
[0033] The node 202 comprises one or more processors 204, a memory
206, a network adapter 210, a cluster access adapter 212, and a
storage adapter 214 interconnected by a system bus 242. The storage
system 200 also includes an operating system 208 installed in the
memory 206 of the node 202 that can, for example, implement a
Redundant Array of Independent (or Inexpensive) Disks (RAID)
optimization technique to optimize a reconstruction process of data
of a failed disk in an array.
[0034] The operating system 208 can also manage communications for
the data storage system, and communications between other data
storage systems that may be in a clustered network, such as
attached to a cluster fabric 215 (e.g., 106 in FIG. 1). Thus, the
node 202, such as a network storage controller, can respond to host
device requests to manage data on the data storage device 234
(e.g., or additional clustered devices) in accordance with these
host device requests. The operating system 208 can often establish
one or more file systems on the data storage system 200, where a
file system can include software code and data structures that
implement a persistent hierarchical namespace of files and
directories, for example. As an example, when a new data storage
device (not shown) is added to a clustered network system, the
operating system 208 is informed where, in an existing directory
tree, new files associated with the new data storage device are to
be stored. This is often referred to as "mounting" a file
system.
[0035] In the example data storage system 200, memory 206 can
include storage locations that are addressable by the processors
204 and adapters 210, 212, 214 for storing related software program
code and data structures. The processors 204 and adapters 210, 212,
214 may, for example, include processing elements and/or logic
circuitry configured to execute the software code and manipulate
the data structures. The operating system 208, portions of which
are typically resident in the memory 206 and executed by the
processing elements, functionally organizes the storage system by,
among other things, invoking storage operations in support of a
file service implemented by the storage system. It will be apparent
to those skilled in the art that other processing and memory
mechanisms, including various computer readable media, may be used
for storing and/or executing program instructions pertaining to the
techniques described herein. For example, the operating system can
also utilize one or more control files (not shown) to aid in the
provisioning of virtual machines.
[0036] The network adapter 210 includes the mechanical, electrical
and signaling circuitry needed to connect the data storage system
200 to a host device 205 over a computer network 216, which may
comprise, among other things, a point-to-point connection or a
shared medium, such as a local area network. The host device 205
(e.g., 108, 110 of FIG. 1) may be a general-purpose computer
configured to execute applications. As described above, the host
device 205 may interact with the data storage system 200 in
accordance with a client/host model of information delivery.
[0037] The storage adapter 214 cooperates with the operating system
208 executing on the node 202 to access information requested by
the host device 205 (e.g., access data on a storage device managed
by a network storage controller). The information may be stored on
any type of attached array of writeable media such as magnetic disk
drives, flash memory, and/or any other similar media adapted to
store information. In the example data storage system 200, the
information can be stored in data blocks on the disks 224, 226,
228. The storage adapter 214 can include input/output (I/O)
interface circuitry that couples to the disks over an I/O
interconnect arrangement, such as a storage area network (SAN)
protocol (e.g., Small Computer System Interface (SCSI), iSCSI,
hyperSCSI, Fiber Channel Protocol (FCP)). The information is
retrieved by the storage adapter 214 and, if necessary, processed
by the one or more processors 204 (or the storage adapter 214
itself) prior to being forwarded over the system bus 242 to the
network adapter 210 (and/or the cluster access adapter 212 if
sending to another node in the cluster) where the information is
formatted into a data packet and returned to the host device 205
over the network connection 216 (and/or returned to another node
attached to the cluster over the cluster fabric 215).
[0038] In one embodiment, storage of information on arrays 218,
220, 222 can be implemented as one or more storage "volumes" 230,
232 that are comprised of a cluster of disks 224, 226, 228 defining
an overall logical arrangement of disk space. The disks 224, 226,
228 that comprise one or more volumes are typically organized as
one or more groups of RAIDs. As an example, volume 230 comprises an
aggregate of disk arrays 218 and 220, which comprise the cluster of
disks 224 and 226.
[0039] In one embodiment, to facilitate access to disks 224, 226,
228, the operating system 208 may implement a file system (e.g.,
write anywhere file system) that logically organizes the
information as a hierarchical structure of directories and files on
the disks. In this embodiment, respective files may be implemented
as a set of disk blocks configured to store information, whereas
directories may be implemented as specially formatted files in
which information about other files and directories are stored.
[0040] Whatever the underlying physical configuration within this
data storage system 200, data can be stored as files within
physical and/or virtual volumes, which can be associated with
respective volume identifiers, such as file system identifiers
(FSIDs), which can be 32-bits in length in one example.
[0041] A physical volume corresponds to at least a portion of
physical storage devices whose address, addressable space,
location, etc. doesn't change, such as at least some of one or more
data storage devices 234 (e.g., a Redundant Array of Independent
(or Inexpensive) Disks (RAID system)). Typically the location of
the physical volume doesn't change in that the (range of)
address(es) used to access it generally remains constant.
[0042] A virtual volume, in contrast, is stored over an aggregate
of disparate portions of different physical storage devices. The
virtual volume may be a collection of different available portions
of different physical storage device locations, such as some
available space from each of the disks 224, 226, and/or 228. It
will be appreciated that since a virtual volume is not "tied" to
any one particular storage device, a virtual volume can be said to
include a layer of abstraction or virtualization, which allows it
to be resized and/or flexible in some regards.
[0043] Further, a virtual volume can include one or more logical
unit numbers (LUNs) 238, directories 236, Qtrees 235, and files
240. Among other things, these features, but more particularly
LUNS, allow the disparate memory locations within which data is
stored to be identified, for example, and grouped as data storage
unit. As such, the LUNs 238 may be characterized as constituting a
virtual disk or drive upon which data within the virtual volume is
stored within the aggregate. For example, LUNs are often referred
to as virtual drives, such that they emulate a hard drive from a
general purpose computer, while they actually comprise data blocks
stored in various parts of a volume.
[0044] In one embodiment, one or more data storage devices 234 can
have one or more physical ports, wherein each physical port can be
assigned a target address (e.g., SCSI target address). To represent
respective volumes stored on a data storage device, a target
address on the data storage device can be used to identify one or
more LUNs 238. Thus, for example, when the node 202 connects to a
volume 230, 232 through the storage adapter 214, a connection
between the node 202 and the one or more LUNs 238 underlying the
volume is created.
[0045] In one embodiment, respective target addresses can identify
multiple LUNs, such that a target address can represent multiple
volumes. The I/O interface, which can be implemented as circuitry
and/or software in the storage adapter 214 or as executable code
residing in memory 206 and executed by the processors 204, for
example, can connect to volume 230 by using one or more addresses
that identify the LUNs 238.
[0046] It may be appreciated that dynamic provisioning of a logical
storage pool may be implemented for the data storage system 200.
For example, a dynamic storage provisioning component may be
implemented for the node 202. The dynamic storage provisioning
component may be configured to automatically and dynamically
provision and/or reprovision storage, such as disks 224, 226,
and/or 228, for use by an application hosted on host device
205.
[0047] One embodiment of dynamically provisioning a logical storage
pool of storage devices for an application is illustrated by an
exemplary method 300 of FIG. 3. A storage environment, such as a
datacenter, may be configured to provide computing resources, such
as data storage, to applications of clients. At 302, a service
level agreement (SLA) for an application, such as a database
application, may be identified. For example, the SLA may specify
performance metrics, desired throughput, acceptable latency, data
loss prevention, and/or other levels of service requested from the
storage environment by the database application.
[0048] At 304, the storage environment may be evaluated to identify
a pool of storage device types that are available for hosting data
of the application. For example, the storage environment may be
queried to determine that various storage devices, such as cloud
storage, a solid state drive (SSD) storage device, virtual storage,
a logical unit number (LUN) array, a tape drive, a serial attached
small computer system interface (SAS) storage device, a serial
advanced technology attachment (SATA) storage device, etc., are
available for hosting database data of the database application. At
306, a logical storage pool, comprising one or more storage devices
selected from the pool of storage devices based upon the SLA, may
be constructed. For example, latency, throughput, revolutions per
minute (RPM), network connection bandwidth to cloud storage, data
loss prevention characteristics, cost, storage size, and/or a
variety of other performance characteristics of storage devices may
be compared to the SLA to identify the one or more storage devices
that have a probability of satisfying the SLA above a threshold
probability (e.g., historical performance statistics, current
real-time performance statistics, and/or manufacturer specification
performance statistics may be evaluated). For example, an SSD
storage device and a 10 k RPM SATA storage device may be selected
for inclusion within the logical storage pool. It may be
appreciated that any number of storage devices may be included
within a logical storage pool, and that any number of logical
storage pools may be constructed for the application.
[0049] At 308, the logical storage pool may be provisioned for the
application. For example, one or more volumes and/or one or more
logical unit numbers (LUNs) may be created across at least one
storage device of the logical storage pool for use by the database
application. In an example, the database application may be
instructed and/or configured to store database data within the
logical storage pool, such as within the SSD storage device and/or
the 10 k RPM SATA storage device (e.g., the database application
may be configured to store data within a volume created within the
logical storage pool). In another example, the storage of the
database data may be transparent to the database application, and
thus the storage environment may be configured to store the
database data within the logical storage pool, such as within the
SSD storage device and/or the 10 k RPM SATA storage device, on
behalf of the database application.
[0050] Real-time performance statistics, associated with the one or
more storage devices of the logical storage pool hosting the data
of the application, may be collected from the storage environment
and/or from the application. The real-time performance statistics
may correspond to latency, throughput, bandwidth, and/or a variety
of other performance metrics associated with operation of the
database application and/or storage of the database data (e.g., a
latency associated with the database application retrieving
database data from the logical storage pool).
[0051] In an example, the real-time performance statistics may be
compared with the SLA to determine whether a storage device does
not satisfy the SLA. For example, latency of the 10 k RPM SATA
storage device may have increased overtime due to an increase in
management of database logs and data, and thus the 10 k RPM SATA
storage device may be identified as not satisfying a latency metric
of the SLA. A replacement storage device, such as cloud storage,
may be identified as a replacement for the 10 k RPM SATA storage
device because the cloud storage may have a probability of
satisfying the SLA above a threshold probability (e.g., measured
latency of the cloud storage may satisfy the latency metric of the
SLA).
[0052] In an example, the replacement storage device may be used to
replace the storage device, and data may be migrated from the
storage device to the replacement storage device (e.g., the cloud
storage may be used to replace the 10 k RPM SATA storage device
within the logical storage pool). In an example of migrating data,
the data may be migrated in a background (e.g., migrated by a
storage controller within the storage environment; migrated by a
background task; migrated by a service as opposed to a front-end
application; etc.) without impacting front-end applications such as
the database application. In another example, a new logical storage
pool may be defined to comprise the storage devices that satisfied
the SLA, such as the SSD storage device, and the replacement
storage device such as the cloud storage used to replace the 10 k
RPM SATA storage device. Data may be migrated (e.g., in the
background) from the 10 k RPM SATA storage device to the cloud
storage. In an example, the new logical storage pool may be
provisioned for the application, such as automatically (e.g.,
without manual intervention or configuration by a storage
administrator) and dynamically during real-time operation of the
storage environment in response to the real-time performance
statistics indicating that the 10 k RPM SATA storage device does
not satisfy the SLA. In another example, the new logical storage
pool may be provided to the storage administrator as a suggestion.
In response to receiving a new provision command from the storage
administrator in response to the suggestion, the migration and
provisioning may be performed. The 10 k RPM SATA storage device may
be released into an available storage pool of the storage
environment for later provisioning for applications.
[0053] In an example where storage resources may have been
overprovisioned, the real-time performance statistics may be
compared with the SLA to identify a storage device that satisfies
the SLA, such as the SSD storage device. A second storage device,
such as a 3.sup.rd party LUN array, may be identified as satisfying
the SLA (e.g., measured performance of the 3.sup.rd party LUN array
may indicate that a latency of the 3.sup.rd party LUN array may be
below the latency metric of the SLA). Responsive to a cost (e.g., a
monetary cost, such as an initial cost, recurring fees, and/or
maintenance costs) of the storage device exceeding a second cost of
the second storage device, a new logical storage pool may be
defined to comprise the storage devices that satisfy the SLA (e.g.,
the cloud storage) and the second storage device, such as the
3.sup.rd party LUN array used to replace the SSD storage device.
Data may be migrated (e.g., in the background) from the SSD storage
device to the 3.sup.rd party LUN array. The new logical storage
pool, comprising the 3.sup.rd party LUN array and the cloud storage
as a replacement for the SSD storage device, may be provisioned for
the application. In this way, costs associated with hosting data of
the application may be reduced without sacrificing performance of
the application.
[0054] In an example, a client may update the SLA for the
application, such as by specifying a new acceptable latency for the
database application accessing database data stored within the
storage environment. Real-time performance statistics may be
compared with the updated SLA to identify a storage device that
does not satisfy the updated SLA. For example, the cloud storage
may be identified as not satisfying the updated SLA. A new logical
storage pool, comprising storage devices that satisfy the updated
SLA and a replacement storage device, such as a second SSD storage
device, used to replace the cloud storage that does not satisfy the
updated SLA, may be defined. Data may be migrated from the cloud
storage to the second SSD storage device. The new logical storage
pool, comprising the second SSD storage device and the 3.sup.rd
party LUN array, may be provisioned for the database
application.
[0055] In an example where multiple logical storage pools may be
provisioned for applications, a set of logical storage pools may be
constructed for the application based upon the SLA. The set of
logical storage pools may be provisioned for the application. In an
example, the set of logical storage pools may comprise a first
logical storage pool, a second logical storage pool, and/or other
logical storage pools. The first logical storage pool may comprise
a first storage device, a second storage device, and/or other
storage devices. The second logical storage pool may comprise a
third storage device, a fourth storage device, and/or other storage
devices. The storage devices of the logical storage pools may have
similar storage device types or dissimilar storage device types
(e.g., the first logical storage pool may comprise cloud storage
and a SATA storage device; the second logical storage pool may
comprise an SSD storage device, etc.). Real-time performance
statistics may be collected for the set of logical storage pools
hosting data of the application. A logical storage pool may be
determined as not satisfying the SLA based upon the real-time
performance statistics. Data may be migrated (e.g., in the
background) from the logical storage pool to a different logical
storage pool (e.g., migrated to a new or existing logical storage
pool) that will satisfy the SLA.
[0056] FIGS. 4A-4E illustrate examples of a system 400, comprising
a dynamic storage provisioning component 422, for dynamically
provisioning one or more logical storage pools of storage devices
for an application 426. FIG. 4A illustrates the dynamic storage
provisioning component 422 identifying a service level agreement
(SLA) 424 for the application 426. The SLA 424 may specify various
data access and/or performance metrics that are to be provided to
the application 426 by a storage environment 402. The dynamic
storage provisioning component 422 may evaluate the storage
environment 402 to identify a pool of storage devices available for
hosting data of the application 426. For example, the pool of
storage devices may comprise a first SSD storage device 404, a
second SSD storage device 406, a tape drive 408, first virtual
storage 410, second virtual storage 412, a first SATA storage
device 414, a second SATA storage device 416, first cloud storage
418, second cloud storage 420, and/or other storage devices or
services.
[0057] FIG. 4B illustrates the dynamic storage provisioning
component 422 constructing a first logical storage pool 430 to
comprise the first SSD storage device 404 and the second cloud
storage 420. The dynamic storage provisioning component 422 may
select the first SSD storage device 404 and the second cloud
storage 420 based upon the storage devices providing data access
and performance that will satisfy the service level agreement 424
of the application 426. For example, real-time performance
statistics, historic performance statistics, and/or manufacture
specified performance statistics may be used by the dynamic storage
provisioning component 422 to select the first SSD storage device
404 and the second cloud storage 420 for inclusion within the first
logical storage pool 430. The dynamic storage provisioning
component 422 may provision the first logical storage pool 430 for
the application 426. In this way, data of the application 426 may
be stored within the first logical storage pool 430 of the storage
environment 402.
[0058] FIG. 4C illustrates the dynamic storage provisioning
component 422 collecting real-time performance statistics 441
corresponding to the first SSD storage device 404 and the second
cloud storage 420 hosting the data of the application 426 (e.g.,
data access latency, throughput, etc.). The dynamic storage
provisioning component 422 may compare the real-time performance
statistics 441 against the service level agreement 424 to determine
whether one or more storage devices within the first logical
storage pool 430, of FIG. 4B, does not satisfy the service level
agreement 424. For example, the dynamic storage provisioning
component 422 may determine that the second cloud storage 420 does
not satisfy the service level agreement 424 (e.g., a cloud storage
service may provide relatively higher latency overtime than what is
specified by the service level agreement 424, such as due to a
network bandwidth decrease by the cloud storage service) based upon
the real-time performance statistics 441.
[0059] Accordingly, the dynamic storage provisioning component 422
may determine that the first SATA storage device 414 may satisfy
the service level agreement 424 (e.g., the first SATA storage
device 414 may have historically provided relatively lower latency
than what is specified by the service level agreement 424). The
dynamic storage provisioning component 422 may construct a second
logical storage pool 440 comprising the first SSD storage device
404 and the first SATA storage device 414 used to replace the
second cloud storage 420. The dynamic storage provisioning
component 422 may migrate data from the second cloud storage 420 to
the first SATA storage device 414, and may provision the second
logical storage pool 440, to replace the first logical storage pool
430, for the application 426. In an example of migrating data, the
data may be migrated in a background (e.g., migrated by a storage
controller within the storage environment 402; migrated by a
background task; migrated by a service as opposed to a front-end
application; etc.) without impacting front-end applications such as
the application 426. The dynamic storage provisioning component 422
may release the second cloud storage 420 into an available storage
pool of the storage environment 402.
[0060] FIG. 4D illustrates an example of the dynamic storage
provisioning component 422 identifying an updated service level
agreement 450 for the application 426. For example, the updated
service level agreement 450 may specify a relatively larger data
throughput than the service level agreement 424. The dynamic
storage provisioning component 422 may collect real-time
performance statistics 451 associated with the second logical
storage pool 440, of FIG. 4C, hosting data of the application 426
within the first SSD storage device 404 and the first SATA storage
device 414. The dynamic storage provisioning component 422 may
evaluate the real-time performance statistics 451 against the
updated service level agreement 450 to determine that the first
SATA storage device 414 does not satisfy the larger data throughput
specified by the updated service level agreement 450.
[0061] Accordingly, the dynamic storage provisioning component 422
may determine that the second SSD storage device 406 may satisfy
the updated service level agreement 451 (e.g., the second SSD
storage device 406 may have historically provided relatively high
throughput bandwidth than what is specified by the updated service
level agreement 450). The dynamic storage provisioning component
422 may construct a third logical storage pool 452 comprising the
first SSD storage device 404 and the second SSD storage device 406
used to replace the first SATA storage device 414. The dynamic
storage provisioning component 422 may migrate data from the first
SATA storage device 414 to the second SSD storage device 406, and
may provision the third logical storage pool 452, to replace the
second logical storage pool 440, for the application 426. The
dynamic storage provisioning component 422 may release the first
SATA storage device 414 into the available storage pool of the
storage environment 402.
[0062] FIG. 4E illustrates an example of the dynamic storage
provisioning component 422 collecting real-time performance
statistics 461 associated with the third logical storage pool 452,
of FIG. 4D, hosting data of the application 426 within the first
SSD storage device 404 and the second SSD storage device 406. The
dynamic storage provisioning component 422 may compare the
real-time performance statistics 461 against the updated service
level agreement 450 to determine that the second SSD storage device
406 satisfies the updated service level agreement 450 and that a
relatively more cost effective storage device may provide similar
performance for the application 426 at a reduced monetary cost. For
example, the dynamic storage provisioning component 422 may
determine that both the second SSD storage device 406 and the first
cloud storage 418 may provide the application 426 with access to
data at a performance level that allows the application 426 to
provide similar responsiveness to clients using the application
426.
[0063] Accordingly, the dynamic storage provisioning component 422
may construct a fourth logical storage pool 460 comprising the
first SSD storage device 404 and the first cloud storage 418 used
to replace the second SSD storage device 406. The dynamic storage
provisioning component 422 may migrate data from the second SSD
storage device 406 to the first cloud storage 418, and may
provision the fourth logical storage pool 460, to replace the third
logical storage pool 452, for the application 426. The dynamic
storage provisioning component 422 may release the second SSD
storage device 406 into the available storage pool of the storage
environment 402.
[0064] FIGS. 5A-5C illustrate examples of a system 500, comprising
a dynamic storage provisioning component 522, for dynamically
provisioning one or more logical storage pools of storage devices
for an application 526. FIG. 5A illustrates the dynamic storage
provisioning component 522 identifying a service level agreement
(SLA) 524 for the application 526. The SLA 524 may specify various
data access and/or performance metrics that are to be provided to
the application 526 by a storage environment 502. The dynamic
storage provisioning component 522 may evaluate the storage
environment 502 to identify a pool of storage devices available for
hosting data of the application 526. For example, the pool of
storage devices may comprise a first SSD storage device 504, a
second SSD storage device 506, a tape drive 508, first virtual
storage 510, second virtual storage 512, a first SATA storage
device 514, a second SATA storage device 516, first cloud storage
518, second cloud storage 520, and/or other storage devices or
services.
[0065] FIG. 5B illustrates the dynamic storage provisioning
component 522 constructing a first logical storage pool 530 to
comprise one or more storage devices of the pool of storage
devices, a second logical storage pool 532 to comprise one or more
storage devices of the pool of storage devices, a third logical
storage pool 534 to comprise one or more storage devices of the
pool of storage devices, and/or other logical storage pools. The
dynamic storage provisioning component 522 may construct the
logical storage pools based upon the service level agreement 524,
such that storage devices within a logical storage pool may satisfy
the service level agreement 524. In this way, data of the
application 526 may be stored within the first logical storage pool
530, the second logical storage pool 532, and/or the third logical
storage pool 534 of the storage environment 502.
[0066] FIG. 5C illustrates the dynamic storage provisioning
component 522 collecting real-time performance statistics 541
corresponding to the first logical storage pool 530, the second
logical storage pool 532, and/or the third logical storage pool 534
hosting data of the application 526. The dynamic storage
provisioning component 522 may compare the real-time performance
statistics 541 against the service level agreement 524 to determine
whether a logical storage pool does not satisfy the service level
agreement 524. For example, the dynamic storage provisioning
component 522 may determine that the third logical storage pool 534
does not satisfy the service level agreement 524 (e.g., a storage
device within the third logical storage pool 534 may provide
relatively higher latency overtime than what is specified by the
service level agreement 524) based upon the real-time performance
statistics 541. Accordingly, the dynamic storage provisioning
component 522 may migrate data of the third logical storage pool
534 to a different logical storage pool, such as a new logical
storage pool or an existing logical storage pool (e.g., the first
logical storage pool 530 and/or the second logical storage pool
523), that may satisfy the service level agreement 524. In an
example of migrating data, the data may be migrated in a background
(e.g., migrated by a storage controller within the storage
environment 502; migrated by a background task; migrated by a
service as opposed to a front-end application; etc.) without
impacting front-end applications such as the application 526. The
dynamic storage provisioning component 522 may remove the third
logical storage pool 534. In this way, logical storage pools that
comprise storage devices that do not satisfy the service level
agreement 524 may be removed so that one or more logical storage
pools that do satisfy the service level agreement 524 may be used
for the application 526.
[0067] Still another embodiment involves a computer-readable medium
comprising processor-executable instructions configured to
implement one or more of the techniques presented herein. An
example embodiment of a computer-readable medium or a
computer-readable device that is devised in these ways is
illustrated in FIG. 6, wherein the implementation 600 comprises a
computer-readable medium 608, such as a CD-R, DVD-R, flash drive, a
platter of a hard disk drive, etc., on which is encoded
computer-readable data 606. This computer-readable data 606, such
as binary data comprising at least one of a zero or a one, in turn
comprises a set of computer instructions 604 configured to operate
according to one or more of the principles set forth herein. In
some embodiments, the processor-executable computer instructions
604 are configured to perform a method 602, such as at least some
of the exemplary method 300 of FIG. 3, for example. In some
embodiments, the processor-executable instructions 604 are
configured to implement a system, such as at least some of the
exemplary system 400 of FIGS. 4A-4E and/or at least some of the
exemplary system 500 of FIGS. 5A-5C, for example. Many such
computer-readable media are contemplated to operate in accordance
with the techniques presented herein.
[0068] It will be appreciated that processes, architectures and/or
procedures described herein can be implemented in hardware,
firmware and/or software. It will also be appreciated that the
provisions set forth herein may apply to any type of
special-purpose computer (e.g., file host, storage server and/or
storage serving appliance) and/or general-purpose computer,
including a standalone computer or portion thereof, embodied as or
including a storage system. Moreover, the teachings herein can be
configured to a variety of storage system architectures including,
but not limited to, a network-attached storage environment and/or a
storage area network and disk assembly directly attached to a
client or host computer. Storage system should therefore be taken
broadly to include such arrangements in addition to any subsystems
configured to perform a storage function and associated with other
equipment or systems.
[0069] In some embodiments, methods described and/or illustrated in
this disclosure may be realized in whole or in part on
computer-readable media. Computer readable media can include
processor-executable instructions configured to implement one or
more of the methods presented herein, and may include any mechanism
for storing this data that can be thereafter read by a computer
system. Examples of computer readable media include (hard) drives
(e.g., accessible via network attached storage (NAS)), Storage Area
Networks (SAN), volatile and non-volatile memory, such as read-only
memory (ROM), random-access memory (RAM), EEPROM and/or flash
memory, CD-ROMs, CD-Rs, CD-RWs, DVDs, cassettes, magnetic tape,
magnetic disk storage, optical or non-optical data storage devices
and/or any other medium which can be used to store data.
[0070] Although the subject matter has been described in language
specific to structural features or methodological acts, it is to be
understood that the subject matter defined in the appended claims
is not necessarily limited to the specific features or acts
described above. Rather, the specific features and acts described
above are disclosed as example forms of implementing at least some
of the claims.
[0071] Various operations of embodiments are provided herein. The
order in which some or all of the operations are described should
not be construed to imply that these operations are necessarily
order dependent. Alternative ordering will be appreciated given the
benefit of this description. Further, it will be understood that
not all operations are necessarily present in each embodiment
provided herein. Also, it will be understood that not all
operations are necessary in some embodiments.
[0072] Furthermore, the claimed subject matter is implemented as a
method, apparatus, or article of manufacture using standard
programming or engineering techniques to produce software,
firmware, hardware, or any combination thereof to control a
computer to implement the disclosed subject matter. The term
"article of manufacture" as used herein is intended to encompass a
computer program accessible from any computer-readable device,
carrier, or media. Of course, many modifications may be made to
this configuration without departing from the scope or spirit of
the claimed subject matter.
[0073] As used in this application, the terms "component",
"module," "system", "interface", and the like are generally
intended to refer to a computer-related entity, either hardware, a
combination of hardware and software, software, or software in
execution. For example, a component includes a process running on a
processor, a processor, an object, an executable, a thread of
execution, a program, or a computer. By way of illustration, both
an application running on a controller and the controller can be a
component. One or more components residing within a process or
thread of execution and a component may be localized on one
computer or distributed between two or more computers.
[0074] Moreover, "exemplary" is used herein to mean serving as an
example, instance, illustration, etc., and not necessarily as
advantageous. As used in this application, "or" is intended to mean
an inclusive "or" rather than an exclusive "or". In addition, "a"
and "an" as used in this application are generally be construed to
mean "one or more" unless specified otherwise or clear from context
to be directed to a singular form. Also, at least one of A and B
and/or the like generally means A or B and/or both A and B.
Furthermore, to the extent that "includes", "having", "has",
"with", or variants thereof are used, such terms are intended to be
inclusive in a manner similar to the term "comprising".
[0075] Many modifications may be made to the instant disclosure
without departing from the scope or spirit of the claimed subject
matter. Unless specified otherwise, "first," "second," or the like
are not intended to imply a temporal aspect, a spatial aspect, an
ordering, etc. Rather, such terms are merely used as identifiers,
names, etc. for features, elements, items, etc. For example, a
first set of information and a second set of information generally
correspond to set of information A and set of information B or two
different or two identical sets of information or the same set of
information.
[0076] Also, although the disclosure has been shown and described
with respect to one or more implementations, equivalent alterations
and modifications will occur to others skilled in the art based
upon a reading and understanding of this specification and the
annexed drawings. The disclosure includes all such modifications
and alterations and is limited only by the scope of the following
claims. In particular regard to the various functions performed by
the above described components (e.g., elements, resources, etc.),
the terms used to describe such components are intended to
correspond, unless otherwise indicated, to any component which
performs the specified function of the described component (e.g.,
that is functionally equivalent), even though not structurally
equivalent to the disclosed structure. In addition, while a
particular feature of the disclosure may have been disclosed with
respect to only one of several implementations, such feature may be
combined with one or more other features of the other
implementations as may be desired and advantageous for any given or
particular application.
* * * * *