U.S. patent application number 15/465656 was filed with the patent office on 2018-09-27 for memory resident storage recovery during computer system failure.
The applicant listed for this patent is International Business Machines Corporation. Invention is credited to Sangeeth Keeriyadath, Nitin Kumar.
Application Number | 20180276077 15/465656 |
Document ID | / |
Family ID | 63295332 |
Filed Date | 2018-09-27 |
United States Patent
Application |
20180276077 |
Kind Code |
A1 |
Keeriyadath; Sangeeth ; et
al. |
September 27, 2018 |
MEMORY RESIDENT STORAGE RECOVERY DURING COMPUTER SYSTEM FAILURE
Abstract
An approach for virtual machine (VM) random access memory (RAM)
disk preservation during VM failure. A RAM disk manager receives a
VM identifier and attributes for connecting a RAM disk to the VM,
where the RAM disk includes a memory region separate from memory
region(s) associated with the VM. The RAM disk manager creates a
RAM disk VM driver for interfacing the RAM disk between a disk
driver and virtual drive adapter. The RAM disk manager detects an
output action based on the disk driver operation and responds to
detecting an output action by storing output data to the RAM disk
and marking synchronization status as pending. The RAM disk manager
synchronizes the output data, asynchronously with non-volatile
storage and detects a failed VM, responding by disconnecting the
RAM disk and can re-assign the RAM disk to a next VM.
Inventors: |
Keeriyadath; Sangeeth;
(Kozhikode, IN) ; Kumar; Nitin; (Bangalore,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
International Business Machines Corporation |
Armonk |
NY |
US |
|
|
Family ID: |
63295332 |
Appl. No.: |
15/465656 |
Filed: |
March 22, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 11/1464 20130101;
G06F 2009/45579 20130101; G06F 9/45558 20130101; G06F 2201/82
20130101; G06F 2201/815 20130101; G06F 3/0619 20130101; G06F
2009/45583 20130101; G06F 2009/45591 20130101; G06F 3/065 20130101;
G06F 11/2046 20130101; G06F 11/2033 20130101; G06F 11/2035
20130101; G06F 11/1451 20130101; G06F 3/0685 20130101 |
International
Class: |
G06F 11/14 20060101
G06F011/14; G06F 3/06 20060101 G06F003/06; G06F 9/455 20060101
G06F009/455 |
Claims
1. A computer-implemented method for virtual machine (VM) random
access memory (RAM) disk preservation during VM failure, the
computer-implemented method comprising: receiving, by a RAM disk
manager, a VM identifier and VM attributes for connecting a RAM
disk to the VM, wherein the RAM disk comprises a memory region
separate from memory region(s) associated with the VM; creating, by
the RAM disk manager, a RAM disk VM driver for interfacing the RAM
disk between a disk driver and virtual drive adapter, wherein the
RAM disk VM driver caches output data and updates metadata,
associated with the RAM disk, indicating completion of output
operations from the VM; detecting, by the RAM disk manager, an
output action based on the disk driver operation; responsive to
detecting the output action, storing, by the RAM disk manager, the
output data from the RAM disk VM driver cache to the RAM disk and
marking synchronization status associated with the output data as
pending; and synchronizing, by the RAM disk manager, the output
data based on the synchronization status of pending, asynchronously
with non-volatile storage associated with the VM and marking the
synchronization status of the output data as complete.
2. The computer-implemented method of claim 1, further comprising:
detecting, by the RAM disk manager, VM operating status of the VM
is failed; and responsive to detecting the VM operating status is
failed, disconnecting, by the RAM disk manager, the RAM disk from
the VM for preventing data corruption of the RAM disk.
3. The computer-implemented method of claim 2, wherein
disconnecting the RAM disk from the VM, further comprising:
synchronizing, by the RAM disk manager, the RAM disk data based on
the synchronization status of pending, with non-volatile storage
associated with the VM and marking the synchronization status of
the output data as complete.
4. The computer-implemented method of claim 2, wherein
disconnecting the RAM disk from the VM, further comprising:
connecting, by the RAM disk manager, the RAM disk to a next VM
replacing the VM; and creating, by the RAM disk manager, a next RAM
disk VM driver for interfacing the RAM disk between a next disk
driver and next virtual drive adapter.
5. The computer-implemented method of claim 1, further comprising:
creating, by the RAM disk manager, the RAM disk based, at least in
part, on the VM identifier, the VM attributes and one or more
predetermined parameters.
6. The computer-implemented method of claim 1, wherein the
synchronization status comprises one or more metadata indicators of
pending or complete to identify the output data storage
synchronization status between the RAM disk and the non-volatile
storage.
7. The computer-implemented method of claim 1, wherein timing
associated with synchronizing the output data is operated in modes
of at least one of real-time based, event based or batch based.
8. A computer-implemented computer program product for virtual
machine (VM) random access memory (RAM) disk preservation during VM
failure, the computer program product comprising: one or more
non-transitory computer readable storage media and program
instructions stored on the one or more non-transitory computer
readable storage media, the program instructions comprising:
program instructions to, receive, by a RAM disk manager, a VM
identifier and VM attributes for connecting a RAM disk to the VM,
wherein the RAM disk comprises a memory region separate from memory
region(s) associated with the VM; program instructions to, create,
by the RAM disk manager, a RAM disk VM driver for interfacing the
RAM disk between a disk driver and virtual drive adapter, wherein
the RAM disk VM driver caches output data and updates metadata,
associated with the RAM disk, indicating completion of output
operations from the VM; program instructions to, detect, by the RAM
disk manager, an output action based on the disk driver operation;
program instructions to, respond to detecting the output action,
storing, by the RAM disk manager, the output data from the RAM disk
VM driver cache to the RAM disk and marking synchronization status
associated with the output data as pending; and program
instructions to, synchronize, by the RAM disk manager, the output
data based on the synchronization status of pending, asynchronously
with non-volatile storage associated with the VM and marking the
synchronization status of the output data as complete.
9. The computer-implemented computer program product of claim 8,
further comprising: program instructions to, detect, by the RAM
disk manager, VM operating status of the VM is failed; and program
instructions to, respond to detecting the VM operating status is
failed, disconnecting, by the RAM disk manager, the RAM disk from
the VM for preventing data corruption of the RAM disk.
10. The computer-implemented computer program product of claim 9,
wherein disconnecting the RAM disk from the VM, further comprising:
program instructions to, synchronize, by the RAM disk manager, the
RAM disk data based on the synchronization status of pending, with
non-volatile storage associated with the VM and marking the
synchronization status of the output data as complete.
11. The computer-implemented computer program product of claim 9,
wherein disconnecting the RAM disk from the VM, further comprising:
program instructions to, connect, by the RAM disk manager, the RAM
disk to a next VM replacing the VM; and program instructions to,
create, by the RAM disk manager, a next RAM disk VM driver for
interfacing the RAM disk between a next disk driver and next
virtual drive adapter.
12. The computer-implemented computer program product of claim 8,
further comprising: program instructions to, create, by the RAM
disk manager, the RAM disk based, at least in part, on the VM
identifier, the VM attributes and one or more predetermined
parameters.
13. The computer-implemented computer program product of claim 8,
wherein the synchronization status comprises one or more metadata
indicators of pending or complete to identify the output data
storage synchronization status between the RAM disk and the
non-volatile storage.
14. The computer-implemented computer program product of claim 8,
wherein timing associated with synchronize the output data is
operated in modes of at least one of real-time based, event based
or batch based.
15. A computer system for virtual machine (VM) random access memory
(RAM) disk preservation during VM failure, the computer system
comprising: one or more computer processors; one or more
non-transitory computer readable storage media; program
instructions stored on the one or more computer non-transitory
readable storage media for execution by at least one of the one or
more computer processors, the program instructions comprising:
program instructions to, receive, by a RAM disk manager, a VM
identifier and VM attributes for connecting a RAM disk to the VM,
wherein the RAM disk comprises a memory region separate from memory
region(s) associated with the VM; program instructions to, create,
by the RAM disk manager, a RAM disk VM driver for interfacing the
RAM disk between a disk driver and virtual drive adapter, wherein
the RAM disk VM driver caches output data and updates metadata,
associated with the RAM disk, indicating completion of output
operations from the VM; program instructions to, detect, by the RAM
disk manager, an output action based on the disk driver operation;
program instructions to, respond to detecting the output action,
storing, by the RAM disk manager, output data from the RAM disk VM
driver cache to the RAM disk and marking synchronization status
associated with the output data as pending; and program
instructions to, synchronize, by the RAM disk manager, the output
data based on the synchronization status of pending, asynchronously
with non-volatile storage associated with the VM and marking the
synchronization status of the output data as complete.
16. The computer system of claim 15, further comprising: program
instructions to, detect, by the RAM disk manager, VM operating
status of the VM is failed; and program instructions to, respond to
detecting the VM operating status is failed, disconnecting, by the
RAM disk manager, the RAM disk from the VM for preventing data
corruption of the RAM disk.
17. The computer system of claim 16, wherein disconnecting the RAM
disk from the VM, further comprising: program instructions to,
synchronize, by the RAM disk manager, the RAM disk data based on
the synchronization status of pending, with non-volatile storage
associated with the VM and marking the synchronization status of
the output data as complete.
18. The computer system of claim 16, wherein disconnecting the RAM
disk from the VM, further comprising: program instructions to,
connect, by the RAM disk manager, the RAM disk to a next VM
replacing the VM; and program instructions to, create, by the RAM
disk manager, a next RAM disk VM driver for interfacing the RAM
disk between a next disk driver and next virtual drive adapter.
19. The computer system of claim 15, further comprising: program
instructions to, create, by the RAM disk manager, the RAM disk
based, at least in part, on the VM identifier, the VM attributes
and one or more predetermined parameters.
20. The computer system of claim 15, wherein the synchronization
status comprises one or more metadata indicators of pending or
complete to identify the output data storage synchronization status
between the RAM disk and the non-volatile storage.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to the field of
virtual machine (VM) management, and more specifically to providing
a hypervisor in a virtualized environment to preserve and restore
RAM disk data during a computer system failure.
[0002] Dynamic Random Access Memory (DRAM) is recognized by one
skilled in the art as a fast/effective method of caching data
blocks as compared to other memory technologies and DRAM can be
used as a caching layer for read/write operations and the DRAM
caching layer can be known in the art as a RAM disk (e.g., a data
storage disk created from DRAM space). DRAM is a
non-persistent/volatile memory and the non-persistence can
contribute to a loss of data in a RAM disk data in the event of a
virtual machine freeze, crash or other failure. During a VM
failure, loss of a RAM disk and the related data loss can weaken
the speed benefits gained by using RAM disk caching for disk
read/write operations in a VM environment.
SUMMARY
[0003] As disclosed herein, a computer-implemented method for
virtual machine (VM) random access memory (RAM) disk preservation
during VM failure, the computer-implemented method comprising:
receiving, by a RAM disk manager, a VM identifier and VM attributes
for connecting a RAM disk to the VM, wherein the RAM disk comprises
a memory region separate from memory region(s) associated with the
VM; creating, by the RAM disk manager, a RAM disk VM driver for
interfacing the RAM disk between a disk driver and virtual drive
adapter; detecting, by the RAM disk manager, an output action based
on the disk driver operation; responsive to detecting an output
action, storing, by the RAM disk manager, output data to the RAM
disk and marking synchronization status associated with the output
data as pending and synchronizing, by the RAM disk manager, the
output data based on the synchronization status of pending,
asynchronously with non-volatile storage associated with the VM and
marking the synchronization status of the output data as complete.
A computer system and a computer program product corresponding to
the above method are also disclosed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The present invention is described in the detailed
description, which follows, references the noted plurality of
drawings by way of non-limiting examples of exemplary embodiments
of the present invention.
[0005] FIG. 1 illustrates a functional block diagram of a computing
environment, in accordance with an embodiment of the present
invention;
[0006] FIG. 2A illustrates a sample architecture of RAMDISK MANAGER
prior to VM failure, in accordance with an embodiment of the
present invention;
[0007] FIG. 2B illustrates a sample architecture of RAMDISK MANAGER
after recovery from VM failure, in accordance with an embodiment of
the present invention;
[0008] FIG. 3 illustrates a flowchart of RAMDISK MANAGER operation,
in accordance with an embodiment of the present invention; and
[0009] FIG. 4 illustrates a block diagram of components of the
server and/or the computing device, in accordance with an
embodiment of the present invention.
DETAILED DESCRIPTION
[0010] Aspects of the present disclosure and certain features,
advantages and details thereof, are explained more fully below with
reference to the non-limiting examples illustrated in the
accompanying figures. Descriptions of well-known materials,
fabrication tools, processing techniques, etc., are omitted to
avoid obscuring the disclosure with unnecessary detail. It should
be understood, however, that the detailed description and the
specific examples, while indicating aspects of the invention, are
given by way of illustration only and not by way of limitation.
Various substitutions, modifications, additions and/or
arrangements, within the spirit and/or scope of the underlying
inventive concepts will be apparent to those skilled in the art
from this disclosure. It should be understood in advance that
although this disclosure includes a detailed description on a
single computer system, implementation of the teachings recited
herein are not limited to a computer system and environment.
Rather, embodiments of the present invention are capable of being
implemented in conjunction with any other type of virtualized
computing environment now known or later developed such as systems
that include multiple computers or clusters of systems on which a
virtualized machine environment can be implemented.
[0011] Embodiments of the present invention provide systems,
methods, and computer program products to improve virtual machine
(VM) data storage speed by interfacing random access memory (RAM)
disk technology with persistent/non-volatile storage while enabling
a mechanism to protect and preserve data from a VM assigned RAM
disk (e.g., memory resident storage) in the event of a VM failure
(e.g., freeze, crash, abnormal loss of VM operation) within a
computer system. Embodiments of the present invention describe a
hypervisor and/or hypervisor module to enable dynamic RAM (DRAM)
and/or RAM to act as a cache layer (e.g., RAM disk) for read and/or
write operations. Embodiments of the present invention comprise a
"RAM disk manager hypervisor/module" which has visibility to a
region of memory used by a VM for caching. It should be noted that
the RAM disk caching memory, formerly described, can be separate
from the memory region used by a VM's operating system and thereby
protects a RAM disk from related VM failures. The RAM disk manager
hypervisor can operate a "RAM disk VM driver module", established
for use by an assigned VM, to enable write caching in the VM by
creating an interface between the VM disk driver and a VM disk
drive adapter driver where the VM disk drive adapter driver can be
used to interface physical data storage (e.g.,
persistent/non-volatile storage) associated with the VM. The "RAM
disk VM driver module" can be resident in a VM and interface
between a disk driver and adapter driver of the VM. The "RAM disk
VM driver module" and cache buffer (e.g., RAM disk) can act as an
intermediate layer to store VM input/output (I/O) data until the
data are actually synchronized, asynchronously, toward non-volatile
storage. It should be noted that RAM disk operation can be
transparent to processing layers such as, but not limited to, VM
applications and disk driver(s). It should be further noted that
RAM disk pending write data can be synchronized asynchronously with
physical data storage. Some embodiments can detect if a VM has
failed and if a VM failure is detected, the RAM disk manager
hypervisor can disconnect the RAM disk from the failed VM, complete
synchronization of write operations toward non-volatile storage and
can further connect the RAM disk to a new VM or back-up VM to
prevent data loss from the RAM disk and to enable continued VM
operation.
[0012] Embodiments of the present invention will now be described
in detail with reference to the figures. It should be noted that
references in the specification to "an exemplary embodiment,"
"other embodiments," etc., indicate that the embodiment described
may include a particular feature, structure, or characteristic, but
every embodiment may not necessarily include the particular
feature, structure, or characteristic. Moreover, such phrases are
not necessarily referring to the same embodiment. Further, when a
particular feature, structure or characteristic is described in
connection with an embodiment, it is submitted that it is within
the knowledge of one skilled in the art to affect such feature,
structure or characteristic in connection with other embodiments
whether or not explicitly described.
[0013] FIG. 1 illustrates a functional block diagram of computing
environment 100, in accordance with an embodiment of the present
invention. Computing environment 100 comprises PHYSICAL DEVICE(S)
110 and COMPUTER SYSTEM 120, interconnected via NETWORK 150.
PHYSICAL DEVICE(S) 110 and COMPUTER SYSTEM 120 can be desktop
computers, laptop computers, specialized computer servers, or the
like. In certain embodiments, PHYSICAL DEVICE(S) 110 and COMPUTER
SYSTEM 120 collectively represent computer systems utilizing
clustered computers and components acting as a single pool of
seamless resources via NETWORK 150. For example, such embodiments
can be used in data center, cloud computing, storage area network
(SAN), and network attached storage (NAS) applications. In general,
PHYSICAL DEVICE(S) 110 and COMPUTER SYSTEM 120 are representative
of any electronic devices, or combination of electronic devices,
capable of executing computer readable program instructions, as
described in detail with regard to FIG. 4.
[0014] In some embodiments, PHYSICAL DEVICE(S) 110 can be a
plurality of PHYSICAL DEVICE(S) 110 and PHYSICAL DEVICE(S) 110 can
be a separate and/or integrated tool that can store data in a
non-volatile manner (e.g., disk drive). In the depicted embodiment,
PHYSICAL DEVICE(S) 110 comprises STORAGE 112 where STORAGE 112 can
comprise any combination of commercial or custom devices and/or
software products associated with accessing and storing data in a
non-volatile method (e.g., storage coherence is persistent after
power is removed).
[0015] In some embodiments, NETWORK 150 comprises, for example, a
local area network (LAN), a wide area network (WAN) such as the
Internet, or a combination of the two, and include wired, wireless,
or fiber optic connections. In general, NETWORK 150 can be any
combination of connections and protocols that can support
communications between PHYSICAL DEVICE(S) 110 and COMPUTER SYSTEM
120, in accordance with some embodiments.
[0016] In some embodiments, COMPUTER SYSTEM 120 comprises
HYPERVISOR 122, VM_A 124, RAMDISK_A 130, VM_B 126 and RAMDISK_B
132. COMPUTER SYSTEM 120 can also comprise a shared host hardware
layer and/or a virtual machine monitor (VMM) which can be
identified as a hypervisor layer (e.g., HYPERVISOR 122). HYPERVISOR
122 further comprises RAMDISK MANAGER 128 and other functions such
as, but not limited to, a VMM (not depicted).
[0017] In some embodiments, HYPERVISOR 122 can be a plurality of
HYPERVISORS 122 within COMPUTER SYSTEM 120. HYPERVISOR 122 can be a
hypervisor layer representing a virtualization layer, operating on
shared host hardware than can create virtual machines and control
the operation and execution of the virtual machine processes and
operations (e.g., VM_A 124, VM_B 126). HYPERVISOR 122 can operate
in conjunction with a combination of commercial or custom devices
and/or software products and can be a separate and/or integrated
tool for managing Virtualized Machines. HYPERVISOR 122 can be
implemented to support the emulation of a physical device to enable
a VM (e.g., VM_A 124, VM_B 126) to communicate with a resource
(e.g., PHYSICAL DEVICE(S) 110). It should be noted that a plurality
of hypervisors can be operated within COMPUTER SYSTEM 120 where the
plurality of HYPERVISOR 122 can manage a variety of computing
functions, independent and/or in cooperation with RAMDISK MANAGER
128.
[0018] In some embodiments, VM_A 124 and VM_B 126 represent Virtual
Machines within COMPUTER SYSTEM 120. It should be noted VM_A 124
and VM_B 126 as depicted, are illustrative of a plurality of
Virtual Machines that can operate within COMPUTER SYSTEM 120. A
virtual machine, known by one skilled in the art, can be described
as an emulation of a computing environment that can be created, run
and/or monitored by a hypervisor software layer operating within a
shared host computer system. In some embodiments, VM_A 124 and/or
VM_B 126 can comprise any combination of commercial or custom
devices and/or software products operational with virtualized
computing environments.
[0019] In some embodiments, RAMDISK MANAGER 128 can be a plurality
of RAMDISK MANAGERS 128 within HYPERVISOR 122. RAMDISK MANAGER 128
can be characterized as module within a hypervisor layer with
operability across a shared operating system and virtual machines
(e.g., VM_A 124, VM_B 126) operated by HYPERVISOR 122. RAMDISK
MANAGER 128 can operate in conjunction with a combination of
commercial or custom devices and/or software products and can be a
separate and/or integrated tool that can be operated to create
and/or manage RAM disk(s) (e.g., RAMDISK_A 130, RAMDISK_B 132) used
in coordination with non-volatile storage. Further, RAMDISK MANAGER
128 can monitor, preserve and/or recover the RAM disk/cached data
that is available during VM operation and/or VM failure (e.g.,
freeze, crash, abnormal loss of VM operation). In the depicted
embodiment, RAMDISK MANAGER 128 comprises, VM MONITOR 138, RECOVERY
ENGINE 140, I/O MONITOR 142 and RAMDISK SYNCHRONIZER 144. It should
be noted that in some embodiments RAMDISK MANAGER 128 can create
and/or operate with VM resident helper module(s) (e.g., a RAM disk
VM driver) to perform at least a portion of the function described
hereinafter by VM MONITOR 138, RECOVERY ENGINE 140, I/O MONITOR 142
and RAMDISK SYNCHRONIZER 144.
[0020] In some embodiments, RAMDISK_A 130 and RAMDISK_B 132 can be
a plurality of RAMDISK_A 130 and RAMDISK_B 132 within COMPUTER
SYSTEM 120. RAMDISK_A 130 and RAMDISK_B 132 represent VM RAM disks
that are assigned/connected to their respective VM (e.g., VM_A 124,
VM_B 126). A RAM disk (e.g., RAMDISK_A 130 and RAMDISK_B 132) can
be established for used by a respective VM to enable read/write
data caching which can improve data storage processing speed while
interfacing physical/non-volatile data storage asynchronously.
RAMDISK_A 130 and RAMDISK_B 132 can be operated in cooperation with
respective VM_A 124, VM_B 126 while operating in memory region(s)
separate from VM_A 124, VM_B 126. Further, RAMDISK MANAGER 128 can
operate creation, connection and management of RAM disks (e.g.,
RAMDISK_A 130, RAMDISK_B 132). It should be noted that a RAM disk
can comprise information such as, but not limited to a metadata
section and a data section. The metadata section can be described
as comprising unique identifiers of the disk(s) being cached by
each VM. The metadata can provide the RAM disk manager hypervisor
(e.g., RAMDISK MANAGER 128) and/or other VMs (e.g., VM_A 124, VM_B
126) in the same system with information to identify the target
disks/non-volatile storage being cached (e.g., RAMDISK_A 130,
RAMDISK_B 132) and which data block(s) in the RAM disk is/are
pending to be synchronized toward non-volatile storage. The data
section can be described as comprising data block(s) to be written
to non-volatile storage. Further, the data section can comprise
unique identifiers to represent the non-volatile storage
destination for the data to be written. It should be noted that
cached data in the RAM disk can be considered "self-sufficient" and
separately allocated from RAMDISK MANAGER 128 and/or a connected VM
so that RAMDISK MANAGER 128 can complete pending write operations
of data to be synchronized in non-volatile storage. In each VM
managed by RAMDISK MANAGER 128, a region of memory used for caching
(e.g., RAMDISK_A 130) can be independently addressable by an
operating system kernel resident driver and a VM counterpart. The
RAM disk memory can be allocated from the system memory for the
related VM and RAMDISK MANAGER 128 can mark and save the
information associated with the RAM disk and/or the VM for which
the RAM disk is connected. It should be noted that it is possible
that the base/host operating system (OS) can use a memory scheme
where Virtual Memory is equal to Real Memory (V=R) or alternatively
described, where a memory address recognized by the OS in a VM
(guest OS) can be the same memory address as recognized by a
hypervisor and/or the host OS.
[0021] In some embodiments, VM MONITOR 138 can be a plurality of VM
MONITORS 138 within RAMDISK MANAGER 128. VM MONITOR 138 can monitor
one or more VM(s) (e.g., VM_A 124, VM_B 126) for failures such as,
but not limited to, freeze, crash, abnormal loss of VM operation.
When a VM failure is detected, VM MONITOR 138 can transfer
operation toward RECOVERY ENGINE 140.
[0022] In some embodiments, RECOVERY ENGINE 140 can be a plurality
of RECOVERY ENGINES 140 within RAMDISK MANAGER 128. RECOVERY ENGINE
140 can perform functions such as, but not limited to, disconnect a
RAM disk associated with a failed VM, create a replacing VM, assign
the RAM disk formerly connected with the failed VM to the replacing
VM or a pre-existing "backup" VM and pass control to RAMDISK
SYNCHRONIZER 144 to complete writing of pending data in the RAM
disk associated with the failed VM. It should be noted that the
replacing VM can be termed as a "next VM" irrespective of the
replacing VM being newly created after a VM failure or the
replacing VM is the pre-existing "backup" VM. In some embodiments,
I/O MONITOR 142 can be a plurality of I/O MONITORS 142 within
RAMDISK MANAGER 128. I/O MONITOR 142 can monitor a VM (e.g., VM_A
124, VM_B 126) for input/output (I/O) activities. When a VM I/O
operation is detected, I/O MONITOR 142 can activate RAMDISK
SYNCHRONIZER 144 to store data in the respectively connected RAM
disk (e.g., RAMDISK_A 130, RAMDISK_B 132) and synchronize RAM disk
data with associated non-volatile storage (e.g., STORAGE 112)
associated with a respective VM (e.g., VM_A 124, VM_B 126).
[0023] In some embodiments, RAMDISK SYNCHRONIZER 144 can be a
plurality of RAMDISK SYNCHRONIZERS 144 within RAMDISK MANAGER 128.
RAMDISK SYNCHRONIZER 144 can store data (e.g., via VM helper module
RAM disk VM driver) toward a connected RAM disk during VM I/O
operations and can determine RAM disk data that are pending to be
written toward non-volatile storage (e.g., STORAGE 112) associated
with a respective VM (e.g., VM_A 124, VM_B 126). It should be noted
that RAMDISK SYNCHRONIZER 144 can operate RAM disk synchronization
with non-volatile storage in an asynchronous mode. Further RAMDISK
SYNCHRONIZER 144 can track pending and/or completed sychronization
operations by methods such as, but not limited to, marking a
synchronization status indicator (e.g., pending, complete) in the
RAM disk metadata, data or by other identifying techniques. It
should be noted that RAMDISK SYNCHRONIZER 144 can operate
asynchronously, operating in modes such as, but not limited to,
real-time based, event based and batch based.
[0024] FIG. 2A illustrates a sample architecture of RAMDISK MANAGER
prior to VM failure, in accordance with an embodiment of the
present invention. RAMDISK MANAGER architecture 200 comprises items
STORAGE 112, HYPERVISOR 122, VM_A 124, RAMDISK MANAGER 128,
RAMDISK_A 130, as described in FIG. 1, and items SHARED HOST OS
202, STORE_ADAPT_A 204, ADAPT_DRV_A 206, RAMDISK VM DRIVER1 208,
APP_1 210, APP_2 212, DISK_DRV_A 214.
[0025] Item SHARED HOST OS 202 illustrates a shared operating
system that operates on COMPUTER SYSTEM 120 and can host/operate a
VM computing system architecture and can provide "real" and/or
"non-virtual" operability with physical storage device(s) (e.g.,
item STORE_ADAPT_A 204). As illustrated, a hypervisor layer (e.g.,
HYPERVISOR 122) can operate item STORE_ADAPT_A 204 by HYPERVISOR
122 operational connection with item SHARED HOST OS 202, which
illustrates a drive/storage adapter (e.g., virtual and/or physical)
that can be associated with a physical storage device (e.g.,
STORAGE 112) and allocated toward a related VM (e.g., VM_A
124).
[0026] Item ADAPT_DRV_A 206 illustrates an emulated/virtual drive
adapter associated with VM_A 124 and can interface with item
STORE_ADAPT_A 204 to operate physical storage device(s) (e.g.,
STORAGE 112).
[0027] Item RAMDISK VM DRIVER1 208 illustrates an interfacing RAM
disk driver operated by RAMDISK MANAGER 128 to manage RAMDISK_A
130. It should be noted that the RAM disk driver (e.g., RAMDISK VM
DRIVER1 208) can cache I/O data that is directed toward
non-volatile storage and can identify attributes such as, but not
limited to, unique ID that can be stored as metadata in the RAM
disk assigned a VM. It should be noted that the RAM disk driver can
perform memory to memory copy of data to/from working memory of a
VM and can update metadata of the RAM disk to indicate completion
of I/O operations.
[0028] Item DISK_DRV_A 214 illustrates disk/storage driver which
can be "visible" to applications within VM_A 122. Further, items
APP_1 210 and APP_2 212 illustrate a plurality of user applications
that can be operated in VM_A 124 and can generate I/O that can be
directed toward STORAGE 112 via item DISK_DRV_A 214. It should be
noted that applications can operate, unmodified, with item
DISK_DRV_A 214 and do not require any special features to recognize
RAMDISK MANAGER 128 operation.
[0029] FIG. 2B illustrates a sample architecture of RAMDISK MANAGER
after recovery from VM failure, in accordance with an embodiment of
the present invention. RAMDISK MANAGER recovered architecture 250
represents a recovery of RAMDISK_A 130 as depicted in FIG. 2A and
comprises items STORAGE 112, HYPERVISOR 122, RAMDISK MANAGER 128,
RAMDISK_A 130, as described in FIG. 1, item SHARED HOST OS 202, as
described in FIG. 2A and items STORE_ADAPT_A2 254, ADAPT_DRV_A2
256, RAMDISK VM DRIVER2 258, APP_1_2 260, APP_2_2 262, DISK_DRV_A2
264, VM_A2 274. RAMDISK MANAGER recovered architecture 250
represents RAMDISK MANAGER architecture 200 after RAMDISK MANAGER
128 detected (e.g., VM MONITOR 138) that VM_A 124 failed. RAMDISK
MANAGER 128 responded to VM_A 124 failure by disconnecting
RAMDISK_A 130 toward VM_A 124. It should be noted that items
STORE_ADAPT_A2 254, ADAPT_DRV_A2 256, RAMDISK VM DRIVER2 258,
APP_1_2 260, APP_2_2 262, DISK_DRV_A2 264 and VM_A2 274 represent
functionally equivalent replacements of respective items
STORE_ADAPT_A 204, ADAPT_DRV_A 206, RAMDISK VM DRIVER1 208, APP_1
210, APP_2 212, DISK_DRV_A 214 and VM_A 124.
[0030] Item VM_A2 274 illustrates a next VM, managed by HYPERVISOR
122, to replace failed item VM_A 124. It should be noted that item
VM_A2 274 can be a pre-existing back up VM or a newly created VM
that HYPERVISOR 122 operates/activates based on failure of item
VM_A 124. Item RAMDISK VM DRIVER2 258 depicts a replacement of item
RAMDISK VM DRIVER1 208 (e.g., re-established via RAMDISK MANAGER
128). Similarly, item ADAPT_DRV_A2 256 depicts a replacement of
item ADAPT_DRV_A 206. RAMDISK MANAGER 128 connects RAMDISK_A 130,
formerly connected toward VM_A 124, now connected toward
replacement item VM_A2 274. Further, RAMDISK MANAGER 128
establishes connection of RAMDISK_A 130 toward item RAMDISK VM
DRIVER2 258 and establishes associating links of item ADAPT_DRV_A2
256 and item DISK_DRV_A2 264. It should be noted that item APP_1_2
260 and item APP_2_2 262 represent similar respective applications
(e.g., item APP_1 210, item APP_2 212) formerly operating in failed
VM_A 124.
[0031] Item STORE_ADAPT_A2 254 illustrates a drive adapter, similar
to item STORE_ADAPT_A 204, that could have been assigned from a
virtual pool of adapters linking STORAGE 112. It should be noted
that RAMDISK MANAGER 128 can complete RAMDISK_A 130 pending write
operations toward STORAGE 112 prior to connecting RAMDISK_A 130
toward VM_A2 274 or after connecting RAMDISK_A 130 toward VM_A2 274
and prior to enabling full operation of item VM_A2 274.
[0032] FIG. 3 illustrates a flowchart of RAMDISK MANAGER operation,
in accordance with an embodiment of the present invention. RAMDISK
MANAGER operation 300, comprises operations RECEIVE VM 302, CREATE
RAMDISK VM DRIVER 304, DETECT VM APP I/O 306, VM RAMDISK WRITE
& SYNCH 308, VM FAILURE 310, DISCONNECT VM RAMDISK 312 and
CREATE NEXT VM & NEXT RAMDISK VM DRIVER 314.
[0033] Operation RECEIVE VM 302, can receive VM identifiers and VM
attributes for a VM (e.g., VM_A 124) to be managed by a RAM disk
manager (e.g., RAMDISK MANAGER 128). When operation RECEIVE VM 302
completes, processing proceeds toward operation CREATE RAMDISK VM
DRIVER 304.
[0034] Operation CREATE RAMDISK VM DRIVER 304, can create a RAM
disk driver (e.g., item RAMDISK VM DRIVER1 208) in the VM to
interface a VM disk driver (e.g., item DISK_DRV_A 214) used by
application(s) (e.g., item APP_1 210, item APP_2 212) with a
connected RAM disk (e.g., RAMDISK_A 130). In some embodiments, RAM
disk manager can create a RAM disk to be connected by to the VM
based on information such as, but not limited to, the VM
identifiers, the VM attributes and one or more predetermined
parameters. It should be noted that the hypervisor operating with
RAMDISK MANAGER 128 can store information about the section/region
of memory assigned to the VM/RAM disk used for RAM disk management.
It should also be noted that operation CREATE RAMDISK VM DRIVER 304
can connect a new RAM disk (e.g., RAMDISK_A 130) or a pre-existing
RAM disk for use with the VM. When operation CREATE RAMDISK VM
DRIVER 304 completes, processing proceeds toward operation DETECT
VM APP I/O 306.
[0035] Operation DETECT VM APP I/O 306, can monitor activities such
as, but not limited to, VM application(s) (e.g., item APP_1 210,
item APP_2 212) and VM disk driver (item DISK_DRV_A 214) for I/O
activity. If an I/O event is detected (e.g., YES) then processing
proceeds toward operation VM RAMDISK WRITE & SYNCH 308.
Otherwise, operation DETECT VM APP I/O 306 processing proceeds
toward operation VM FAILURE 310.
[0036] Operation VM RAMDISK WRITE & SYNCH 308, can write I/O
data (e.g., RAMDISK SYNCHRONIZER 144), received toward the RAM disk
VM driver (e.g., item RAMDISK VM DRIVER1 208), toward the RAM disk
and the data can be synchronized/written toward non-volatile
storage (e.g., STORAGE 112) identified as the destination of data
block storage operation. When operation VM RAMDISK WRITE &
SYNCH 308 completes, processing proceeds toward operation VM
FAILURE 310.
[0037] Operation VM FAILURE 310, can monitor VM failure (e.g.,
crash, freeze), if VM failure occurs (e.g., YES) then, processing
proceeds toward operation DISCONNECT VM RAMDISK 312. Otherwise,
operation VM FAILURE 310 processing proceeds toward operation
DETECT VM APP I/O 306.
[0038] Operation DISCONNECT VM RAMDISK 312, can disconnect the RAM
disk memory assigned toward the failed VM via RECOVERY ENGINE 140
to prevent corruption of RAM disk memory/data and remaining pending
write operations comprising the RAM disk (e.g., RAMDISK_A 130) can
be completed toward STORAGE 112 via RECOVERY ENGINE 140. When
operation DISCONNECT VM RAMDISK 312 completes, processing proceeds
toward operation CREATE NEXT VM & NEXT RAMDISK VM DRIVER
314.
[0039] Operation CREATE NEXT VM & NEXT RAMDISK VM DRIVER 314,
can create a new replacement VM (e.g., next VM) and/or respond to
the creation of the next VM to create a next RAM disk driver (e.g.,
item RAMDISK VM DRIVER2 258), replacing a failed VM (e.g., VM_A
124). Processing can be similar to operation CREATE RAMDISK VM
DRIVER 304 where the RAM disk connected toward the failed VM can be
connected toward the next VM and interfaced with the RAM disk
driver (e.g., item RAMDISK VM DRIVER2 258) and physical storage
(e.g., STORAGE 112) via an adapter driver (e.g., item ADAPT_DRV_A2
256). It should be noted that in some embodiments, the next VM can
be pre-defined as a "hot" backup and operation CREATE NEXT VM &
NEXT RAMDISK VM DRIVER 314 can bypass creation of the next VM and
execute a connection of the RAM disk toward the replacing
pre-defined next VM. When operation CREATE NEXT VM & NEXT
RAMDISK VM DRIVER 314 completes, processing proceeds toward END or
can loop toward operation DETECT VM APP I/O 306 for continuous
execution mode for a life-cycle of a VM.
[0040] FIG. 4 illustrates a block diagram of components of PHYSICAL
DEVICE(S) 110 and COMPUTER SYSTEM 120 in accordance with an
illustrative embodiment of the present invention. It should be
appreciated that FIG. 4 provides only an illustration of one
implementation and does not imply any limitations with regard to
the environments in which different embodiments may be implemented.
Many modifications to the depicted environment may be made.
[0041] Computer system 400 includes communications fabric 402,
which provides communications between computer processor(s) 404,
memory 406, persistent storage 408, communications unit 410, and
input/output (I/O) interface(s) 412. Communications fabric 402 can
be implemented with any architecture designed for passing data
and/or control information between processors (such as
microprocessors, communications and network processors, etc.),
system memory, peripheral devices, and any other hardware
components within a system. For example, communications fabric 402
can be implemented with one or more buses.
[0042] Computer system 400 includes processors 404, cache 416,
memory 406, persistent storage 408, communications unit 410,
input/output (I/O) interface(s) 412 and communications fabric 402.
Communications fabric 402 provides communications between cache
416, memory 406, persistent storage 408, communications unit 410,
and input/output (I/O) interface(s) 412. Communications fabric 402
can be implemented with any architecture designed for passing data
and/or control information between processors (such as
microprocessors, communications and network processors, etc.),
system memory, peripheral devices, and any other hardware
components within a system. For example, communications fabric 402
can be implemented with one or more buses or a crossbar switch.
[0043] Memory 406 and persistent storage 408 are computer readable
storage media. In this embodiment, memory 406 includes random
access memory (RAM). In general, memory 406 can include any
suitable volatile or non-volatile computer readable storage media.
Cache 416 is a fast memory that enhances the performance of
processors 404 by holding recently accessed data, and data near
recently accessed data, from memory 406.
[0044] Program instructions and data used to practice some
embodiments may be stored in persistent storage 408 and in memory
406 for execution by one or more of the respective processors 404
via cache 416. In an embodiment, persistent storage 408 includes a
magnetic hard disk drive. Alternatively, or in addition to a
magnetic hard disk drive, persistent storage 408 can include a
solid state hard drive, a semiconductor storage device, read-only
memory (ROM), erasable programmable read-only memory (EPROM), flash
memory, or any other computer readable storage media that is
capable of storing program instructions or digital information.
[0045] The media used by persistent storage 408 may also be
removable. For example, a removable hard drive may be used for
persistent storage 408. Other examples include optical and magnetic
disks, thumb drives, and smart cards that are inserted into a drive
for transfer onto another computer readable storage medium that is
also part of persistent storage 408.
[0046] Communications unit 410, in these examples, provides for
communications with other data processing systems or devices. In
these examples, communications unit 410 includes one or more
network interface cards. Communications unit 410 may provide
communications through the use of either or both physical and
wireless communications links. Program instructions and data used
to practice some embodiments may be downloaded to persistent
storage 408 through communications unit 410.
[0047] I/O interface(s) 412 allows for input and output of data
with other devices that may be connected to each computer system.
For example, I/O interface 412 may provide a connection to external
devices 418 such as a keyboard, keypad, a touch screen, and/or some
other suitable input device. External devices 418 can also include
portable computer readable storage media such as, for example,
thumb drives, portable optical or magnetic disks, and memory cards.
Software and data used to practice some embodiments can be stored
on such portable computer readable storage media and can be loaded
onto persistent storage 408 via I/O interface(s) 412. I/O
interface(s) 412 also connect to display 420.
[0048] Display 420 provides a mechanism to display data to a user
and may be, for example, a computer monitor.
[0049] The programs described herein are identified based upon the
application for which they are implemented in a specific embodiment
of the invention. However, it should be appreciated that any
particular program nomenclature herein is used merely for
convenience, and thus the invention should not be limited to use
solely in any specific application identified and/or implied by
such nomenclature.
[0050] The present invention may be a system, a method, and/or a
computer program product. The computer program product may include
a computer readable storage medium (or media) having computer
readable program instructions thereon for causing a processor to
carry out aspects of the present invention.
[0051] The computer readable storage medium can be a tangible
device that can retain and store instructions for use by an
instruction execution device. The computer readable storage medium
may be, for example, but is not limited to, an electronic storage
device, a magnetic storage device, an optical storage device, an
electromagnetic storage device, a semiconductor storage device, or
any suitable combination of the foregoing. A non-exhaustive list of
more specific examples of the computer readable storage medium
includes the following: a portable computer diskette, a hard disk,
a random access memory (RAM), a read-only memory (ROM), an erasable
programmable read-only memory (EPROM or Flash memory), a static
random access memory (SRAM), a portable compact disc read-only
memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a
floppy disk, a mechanically encoded device such as punch-cards or
raised structures in a groove having instructions recorded thereon,
and any suitable combination of the foregoing. A computer readable
storage medium, as used herein, is not to be construed as being
transitory signals per se, such as radio waves or other freely
propagating electromagnetic waves, electromagnetic waves
propagating through a waveguide or other transmission media (e.g.,
light pulses passing through a fiber-optic cable), or electrical
signals transmitted through a wire.
[0052] Computer readable program instructions described herein can
be downloaded to respective computing/processing devices from a
computer readable storage medium or to an external computer or
external storage device via a network, for example, the Internet, a
local area network, a wide area network and/or a wireless network.
The network may comprise copper transmission cables, optical
transmission fibers, wireless transmission, routers, firewalls,
switches, gateway computers and/or edge servers. A network adapter
card or network interface in each computing/processing device
receives computer readable program instructions from the network
and forwards the computer readable program instructions for storage
in a computer readable storage medium within the respective
computing/processing device.
[0053] Computer readable program instructions for carrying out
operations of the present invention may be assembler instructions,
instruction-set-architecture (ISA) instructions, machine
instructions, machine dependent instructions, microcode, firmware
instructions, state-setting data, or either source code or object
code written in any combination of one or more programming
languages, including an object oriented programming language such
as Smalltalk, C++ or the like, and conventional procedural
programming languages, such as the "C" programming language or
similar programming languages. The computer readable program
instructions may execute entirely on the user's computer, partly on
the user's computer, as a stand-alone software package, partly on
the user's computer and partly on a remote computer or entirely on
the remote computer or server. In the latter scenario, the remote
computer may be connected to the user's computer through any type
of network, including a local area network (LAN) or a wide area
network (WAN), or the connection may be made to an external
computer (for example, through the Internet using an Internet
Service Provider). In some embodiments, electronic circuitry
including, for example, programmable logic circuitry,
field-programmable gate arrays (FPGA), or programmable logic arrays
(PLA) may execute the computer readable program instructions by
utilizing state information of the computer readable program
instructions to personalize the electronic circuitry, in order to
perform aspects of the present invention.
[0054] Aspects of the present invention are described herein with
reference to flowchart illustrations and/or block diagrams of
methods, apparatus (systems), and computer program products
according to embodiments of the invention. It will be understood
that each block of the flowchart illustrations and/or block
diagrams, and combinations of blocks in the flowchart illustrations
and/or block diagrams, can be implemented by computer readable
program instructions.
[0055] These computer readable program instructions may be provided
to a processor of a general purpose computer, special purpose
computer, or other programmable data processing apparatus to
produce a machine, such that the instructions, which execute via
the processor of the computer or other programmable data processing
apparatus, create means for implementing the functions/acts
specified in the flowchart and/or block diagram block or blocks.
These computer readable program instructions may also be stored in
a computer readable storage medium that can direct a computer, a
programmable data processing apparatus, and/or other devices to
function in a particular manner, such that the computer readable
storage medium having instructions stored therein comprises an
article of manufacture including instructions which implement
aspects of the function/act specified in the flowchart and/or block
diagram block or blocks.
[0056] The computer readable program instructions may also be
loaded onto a computer, other programmable data processing
apparatus, or other device to cause a series of operational steps
to be performed on the computer, other programmable apparatus or
other device to produce a computer implemented process, such that
the instructions which execute on the computer, other programmable
apparatus, or other device implement the functions/acts specified
in the flowchart and/or block diagram block or blocks.
[0057] The flowchart and block diagrams in the figures illustrate
the architecture, functionality, and operation of possible
implementations of systems, methods, and computer program products
according to various embodiments. In this regard, each block in the
flowchart or block diagrams may represent a module, segment, or
portion of instructions, which comprises one or more executable
instructions for implementing the specified logical function(s). In
some alternative implementations, the functions noted in the block
may occur out of the order noted in the figures. For example, two
blocks shown in succession may, in fact, be executed substantially
concurrently, or the blocks may sometimes be executed in the
reverse order, depending upon the functionality involved. It will
also be noted that each block of the block diagrams and/or
flowchart illustration, and combinations of blocks in the block
diagrams and/or flowchart illustration, can be implemented by
special purpose hardware-based systems that perform the specified
functions or acts or carry out combinations of special purpose
hardware and computer instructions.
[0058] The descriptions of the various embodiments been presented
for purposes of illustration, but are not intended to be exhaustive
or limited to the embodiments disclosed. Many modifications and
variations will be apparent to those of ordinary skill in the art
without departing from the scope and spirit of the invention. The
terminology used herein was chosen to best explain the principles
of the embodiment, the practical application or technical
improvement over technologies found in the marketplace, or to
enable others of ordinary skill in the art to understand the
embodiments disclosed herein.
[0059] In different embodiments, the claimed subject matter may be
implemented as a combination of both hardware and software
elements, or alternatively either entirely in the form of hardware
or entirely in the form of software. Further, computing systems and
program software disclosed herein may comprise a controlled
computing environment that may be presented in terms of hardware
components or logic code executed to perform methods and processes
that achieve the results contemplated herein. Said methods and
processes, when performed by a general purpose computing system or
machine, convert the general purpose machine to a specific purpose
machine.
[0060] The descriptions of the various embodiments of the present
invention have been presented for purposes of illustration, but are
not intended to be exhaustive or limited to the embodiments
disclosed. Many modifications and variations will be apparent to
those of ordinary skill in the art without departing from the scope
and spirit of the invention. The terminology used herein was chosen
to best explain the principles of the embodiment, the practical
application or technical improvement over technologies found in the
marketplace, or to enable others of ordinary skill in the art to
understand the embodiments disclosed herein.
[0061] The term "present invention" should not be taken as an
absolute indication that the subject matter described by the term
"present invention" is covered by either the claims as they are
filed, or by the claims that may eventually issue after patent
prosecution; while the term "present invention" is used to help the
reader to get a general feel for which disclosures herein are
believed to potentially be new, this understanding, as indicated by
use of the term "present invention," is tentative and provisional
and subject to change over the course of patent prosecution as
relevant information is developed and as the claims are potentially
amended.
[0062] The term "and/or" should be understood as inclusive or; for
example, A, B "and/or" C means that at least one of A, B or C is
true and applicable. Further, "at least one of A, B, or C" should
be interpreted to mean only A, only B, only C, or any combination
of A, B, and C.
* * * * *