U.S. patent application number 13/494382 was filed with the patent office on 2012-10-04 for backup memory administration.
This patent application is currently assigned to INTERNATIONAL BUSINESS MACHINES CORPORATION. Invention is credited to Jeffrey R. Hamilton, Melba I. Lopez, Ross L. Mickens, Markesha F. Parker.
Application Number | 20120254521 13/494382 |
Document ID | / |
Family ID | 46065489 |
Filed Date | 2012-10-04 |
United States Patent
Application |
20120254521 |
Kind Code |
A1 |
Hamilton; Jeffrey R. ; et
al. |
October 4, 2012 |
Backup Memory Administration
Abstract
Methods, systems, and computer program products for backup
memory administration are provided. Embodiments include storing in
an active memory device, by a memory backup controller, blocks of
computer data received from random access memory; recording in a
change log, by the memory backup controller, identifications of
each block of computer data that is stored in the active memory
device; detecting, by the memory backup controller, a backup
trigger event; and responsive to the detecting of the backup
trigger event: copying, by the memory backup controller, from the
active memory device, to a backup memory device, the blocks of data
identified in the change log; and clearing, by the memory backup
controller, the change log.
Inventors: |
Hamilton; Jeffrey R.;
(Pittsboro, NC) ; Lopez; Melba I.; (Raleigh,
NC) ; Mickens; Ross L.; (Cary, NC) ; Parker;
Markesha F.; (Durham, NC) |
Assignee: |
INTERNATIONAL BUSINESS MACHINES
CORPORATION
ARMONK
NY
|
Family ID: |
46065489 |
Appl. No.: |
13/494382 |
Filed: |
June 12, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12949405 |
Nov 18, 2010 |
|
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13494382 |
|
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Current U.S.
Class: |
711/103 ;
711/162; 711/E12.008; 711/E12.103 |
Current CPC
Class: |
G06F 11/1662 20130101;
G06F 11/2094 20130101 |
Class at
Publication: |
711/103 ;
711/162; 711/E12.103; 711/E12.008 |
International
Class: |
G06F 12/16 20060101
G06F012/16 |
Claims
1. A method of backup memory administration comprising: storing in
an active memory device, by a memory backup controller, blocks of
computer data received from random access memory; recording in a
change log, by the memory backup controller, identifications of
each block of computer data that is stored in the active memory
device; detecting, by the memory backup controller, a backup
trigger event; and responsive to the detecting of the backup
trigger event: copying, by the memory backup controller, from the
active memory device, to a backup memory device, the blocks of data
identified in the change log; and clearing, by the memory backup
controller, the change log.
2. The method of claim 1, further comprising: detecting, by the
memory backup controller, a bad block in the active memory device;
ceasing, by the memory backup controller, usage of the bad block in
the active memory device; switching, by the memory backup
controller, a designation of the backup memory device from backup
usage to active usage; and switching, by the memory backup
controller, a designation of the active memory device from active
usage to backup usage.
3. The method of claim 2, further comprising: receiving, by the
memory backup controller, additional blocks of computer data from
the random access memory; responsive to the designations of the
active memory device and the backup memory device, storing, by the
memory backup controller, the additional blocks of computer data on
a memory device designated as being in active usage.
4. The method of claim 1, wherein the backup trigger event is
triggered in response to an expiration of a predetermined period of
time.
5. The method of claim 1, wherein the backup trigger event is
triggered in response to a change in a power state of one of the
processor and the memory backup controller.
6. The method of claim 1, wherein the backup trigger event is
triggered in response to an occurrence of a particular time.
7. The method of claim 1, wherein the backup trigger event is
triggered in response to the change log reaching a storage
capacity.
8. The method of claim 1, wherein the memory backup controller is
coupled to the processor through an expansion bus.
9. The method of claim 1, wherein the expansion bus includes a type
selected from the group consisting of a universal serial bus (USB),
a small computer system interface (SCSI) bus, a peripheral
component interconnect express (PCIe) bus, and a parallel
attachment packet interface (ATAPI) bus.
10. The method of claim 1, wherein the active memory device and the
backup memory device include flash memory.
11-20. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation application of and claims
priority from U.S. patent application Ser. No. 12/949,405, filed on
Nov. 18, 2010.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The field of the invention is data processing, or, more
specifically, methods, systems, and computer program products for
backup memory administration.
[0004] 2. Description of Related Art
[0005] Flash memory devices have a finite number of erase-write
cycles. Most commercially available flash memory devices are
guaranteed to withstand around 100,000 write-erase cycles before
the wear begins to deteriorate the integrity of the memory device.
Deterioration in the integrity of the memory device may result in
loss of data.
SUMMARY OF THE INVENTION
[0006] Methods, systems, and computer program products for backup
memory administration are provided. Embodiments include storing in
an active memory device, by a memory backup controller, blocks of
computer data received from random access memory; recording in a
change log, by the memory backup controller, identifications of
each block of computer data that is stored in the active memory
device; detecting, by the memory backup controller, a backup
trigger event; and responsive to the detecting of the backup
trigger event: copying, by the memory backup controller, from the
active memory device, to a backup memory device, the blocks of data
identified in the change log; and clearing, by the memory backup
controller, the change log.
[0007] The foregoing and other objects, features and advantages of
the invention will be apparent from the following more particular
descriptions of exemplary embodiments of the invention as
illustrated in the accompanying drawings wherein like reference
numbers generally represent like parts of exemplary embodiments of
the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 sets forth a diagram of an example computer for
backup memory administration according to embodiments of the
present invention.
[0009] FIG. 2 sets forth a flow chart illustrating an exemplary
method for backup memory administration according to embodiments of
the present invention.
[0010] FIG. 3 sets forth a flow chart illustrating another
exemplary method for backup memory administration according to
embodiments of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0011] Exemplary methods, apparatuses, and products for backup
memory administration in accordance with the present invention are
described with reference to the accompanying drawings, beginning
with FIG. 1. FIG. 1 sets forth a diagram of a example computer
(101) for backup memory administration according to embodiments of
the present invention. The example computer (101) of FIG. 1
includes a processor (140) or `CPU` as well as random access memory
(168) (`RAM`), which is connected through a high speed memory bus
(166) and bus adapter (158) to the processor (140), and connected
to a memory backup controller (102) through an expansion bus
(110).
[0012] Stored in RAM (168) is an operating system (154). Operating
systems useful for backup memory administration according to
embodiments of the present invention include UNIX.TM., Linux.TM.,
Microsoft XP.TM., AIX.TM., IBM's i5/OS.TM., and others as will
occur to those of skill in the art. The operating system (154) is
shown in RAM (168), but many components of such software typically
are stored in non-volatile memory also, such as, for example, on a
disk drive (170).
[0013] The example computer (101) of FIG. 1 includes a disk drive
adapter (172) coupled through the expansion bus (110) and the bus
adapter (158) to the processor (140) and other components of the
example computer (101). The disk drive adapter (172) connects
non-volatile data storage to the example computer (101) in the form
of the disk drive (170). Disk drive adapters useful in computers
for backup memory administration according to embodiments of the
present invention include Integrated Drive Electronics (`IDE`)
adapters, Small Computer System Interface (`SCSI`) adapters, and
others as will occur to those of skill in the art. Non-volatile
computer memory also may be implemented for as an optical disk
drive, electrically erasable programmable read-only memory
(so-called `EEPROM` or `Flash` memory), RAM drives, and so on, as
will occur to those of skill in the art.
[0014] The example computer (101) of FIG. 1 includes one or more
input/output (`I/O`) adapters (178). I/O adapters implement
user-oriented input/output through, for example, software drivers
and computer hardware for controlling output to display devices
such as computer display screens. The example computer (101) of
FIG. 1 includes a video adapter (109), which is an example of an
I/O adapter specially designed for graphic output to a display
device (180) such as a display screen or computer monitor. The
video adapter (109) is connected to the processor (140) through a
high speed video bus (164), bus adapter (158), and the front side
bus (162), which is also a high speed bus.
[0015] The example computer (101) of FIG. 1 includes a
communications adapter (167) for data communications with other
computers (182) and for data communications with a data
communications network (106). Such data communications may be
carried out serially through RS-232 connections, through external
buses such as a Universal Serial Bus (`USB`), through data
communications data communications networks such as IP data
communications networks, and in other ways as will occur to those
of skill in the art. Communications adapters implement the hardware
level of data communications through which one computer sends data
communications to another computer, directly or through a data
communications network. Examples of communications adapters useful
for backup memory administration according to embodiments of the
present invention include modems for wired dial-up communications,
Ethernet (IEEE 802.3) adapters for wired data communications
network communications, and 802.11 adapters for wireless data
communications network communications.
[0016] The processor (140) of FIG. 1 is configured to transfer data
over the expansion bus (110) to the memory backup controller (102).
An expansion bus includes electronic pathways which move
information between components of a computer system. The expansion
bus (110) of FIG. 1 may be any type of bus that establishes
communication between a device and a host controller. For example,
the expansion bus (110) may be a universal serial bus (USB), a
small computer system interface (SCSI) bus, a peripheral component
interconnect express (PCIe) bus, a parallel attachment packet
interface (ATAPI) bus, and so on. The processor (140) and the
memory backup controller (102) of FIG. 1 each include an interface
for connection to the expansion bus (110). An interface is a point
of interaction between two devices or pathways. The processor (140)
and the memory backup controller (102) of FIG. 1 may include a USB
interface, a SCSI interface, a PCIe interface, a ATAPI interface,
and so on.
[0017] The memory backup controller (102) of FIG. 1 is configured
to route blocks of computer data (120) received from the random
access memory (RAM) (168) over the expansion bus (110) to either an
active memory device (104) or a backup memory device (106). A
memory backup controller is a digital circuit which manages the
flow of data going to and from memory storage devices. A memory
storage device typically consists of a small printed circuit board
that includes flash memory and a connector, such as a USB
interface, for communicating with the memory backup controller
(102). The memory backup controller (102) is configured to
designate the memory storage devices (104, 106) as either being in
active usage or backup usage. The active memory device (104) of
FIG. 1 is in active usage and the backup memory device (106) is in
backup usage. When the active flash storage device (104) is
operational, the memory backup controller (102) stores the blocks
of computer data (120) on the active flash storage device (104).
When the active flash storage device (104) is not operational and
the backup flash storage device (106) is operational, the memory
backup controller (102) stores the blocks of computer data (120) on
the backup flash storage device (106).
[0018] The memory backup controller (102) of FIG. 1 includes a
change log (108). The change log (108) includes identifications of
each block of data written to the active memory device (104). When
the memory backup controller (102) writes the blocks of computer
data (120) to the active storage device (104), the memory backup
controller (102) is configured to store in the change log (108),
the identifications of each block of data written to the active
memory device (104).
[0019] The memory backup controller (102) of FIG. 1 is configured
to detect a backup trigger event. A backup trigger event may be
triggered in response to any number of conditions, such as an
expiration of a predetermined period of time, a change in the power
state of the processor (140) or one of the memory devices (104,
106), occurrence of a particular time, detection that the change
log is full of recordings. In response to detecting a backup
trigger event, the backup memory controller (102) is configured to
copy, from the active memory device (104), to the backup memory
device (106), all blocks of data identified in the change log
(108). The backup memory controller (102) of FIG. 1 is also
configured to clear the change log (108) in response to detecting
the backup trigger event.
[0020] The memory backup controller (102) of FIG. 1 is also
configured to detect a bad block of data in the active memory
device (104). The backup trigger event may include an electronic
signal sent from one or more components of the example computer
(101). A bad block of data includes a single bit error or multi-bit
errors. In response to detecting a bad block of data in the active
memory device (104), the memory backup controller (102) records an
identification associated with the detected bad block, stops using
the bad block in the active memory device (106), and switches the
backup memory device (106) to active usage and the active memory
device (104) to backup usage.
[0021] For further explanation, FIG. 2 sets forth a flow chart
illustrating an exemplary method for backup memory administration
according to embodiments of the present invention. The method of
FIG. 2 includes storing (202) in an active memory device (104), by
a memory backup controller (102), blocks of computer data (120)
received from RAM (168). Storing (202) in the active memory device
(104) the blocks of the computer data (120) received from random
access memory (168) may be carried out by receiving the blocks of
computer data (120) over the expansion bus (110) from the random
access memory (168), establishing a connection between the memory
backup controller (102) and the active memory device (104), and
transmitting the received blocks of computer data (120) to the
active memory device (104).
[0022] The method of FIG. 2 also includes recording (204) in a
change log (108), by the memory backup controller (102),
identifications (206) of each block of computer data (120) that is
stored in the active memory device (104). Recording (204) in the
change log (108) the identifications (206) of each block of
computer data (120) that is stored in the active memory device
(104) may be carried out by tracking transmission of blocks of data
to the active memory device (104), storing identifications (206) of
blocks that are stored in the active memory device (104), and
storing in local memory in the memory backup controller (102) the
identifications (206) within the memory backup controller
(102).
[0023] The method of FIG. 2 includes detecting (208), by the memory
backup controller (102), a backup trigger event (210). Detecting
(208) a backup trigger event (210) may be carried out by receiving
a command from a processor via the expansion bus (110) indicating
that a backup trigger event (210) is occurring, comparing a current
time with a predetermined time, and determining a storage capacity
level of the change log (108).
[0024] The method of FIG. 2 includes responsive to detecting (208)
of the backup trigger event (210), copying (212), by the memory
backup controller (102), from the active memory device (104), to a
backup memory device (106), the blocks of data identified in the
change log (108). Copying (212) from the active memory device (104)
to the backup memory device (106), the block of data identified in
the change log (108) may be carried out by establishing a
connection between the memory backup controller (102) and the
active memory device (104), receiving the identified blocks of data
from the active memory device (104), temporarily storing the
identified blocks of data (12), and transmitting the blocks of data
(120) to the backup memory device (106).
[0025] The method of FIG. 2 includes responsive to the detecting
(208) of the backup trigger event (210), clearing (214), by the
memory backup controller (102), the change log (108). Clearing
(214) the change log (108) may be carried out by resetting bits of
data within the change log (108) and changing values of variables
within or associated with the change log (108).
[0026] For further explanation, FIG. 3 sets forth a flow chart
illustrating another exemplary method for backup memory
administration according to embodiments of the present invention.
The method of FIG. 3 includes the following elements of the method
of FIG. 2: storing (202) in an active memory device (104), by a
memory backup controller (102), blocks of computer data (120)
received from random access memory (168); recording (204) in a
change log (108), by the memory backup controller (102),
identifications (206) of each block of computer data that is stored
in the active memory device (104); detecting (208), by the memory
backup controller (102), a backup trigger event (210); responsive
to the detecting of the backup trigger event (210), copying (212),
by the memory backup controller (102), from the active memory
device (104), to a backup memory device (106), the blocks of data
identified in the change log (108); and responsive to the detecting
of the backup trigger event, clearing (214), by the memory backup
controller (102), the change log (108).
[0027] The elements of FIG. 3 that differ from the method of FIG. 2
are illustrated in FIG. 3 with a dashed line. More particularly,
those elements include: detecting (302), by the memory backup
controller (102), a bad block (304) in the active memory device
(104); ceasing (306), by the memory backup controller (102), usage
of the bad block (304) in the active memory device (104); switching
(308), by the memory backup controller (102), a designation of the
backup memory device (106) from backup usage to active usage; and
switching (310), by the memory backup controller (102), a
designation of the active memory device (104) from active usage to
backup usage.
[0028] The method of FIG. 3 includes detecting (302), by the memory
backup controller (102), a bad block (304) in the active memory
device (104). Detecting (302) a bad block (304) in the active
memory device (104) may be carried out by receiving error
correction codes (ECC) data from the active memory device (104) and
determining if the ECC data indicates a bad block of data within
the active memory device (104).
[0029] The method of FIG. 3 also includes ceasing (306), by the
memory backup controller (102), usage of the bad block (304) in the
active memory device (104). Ceasing (306) the usage of the bad
blocks (304) in the active memory device (104) may be carried out
by the memory backup controller (102) changing a bit to indicate
that the active memory device (104) includes a bad block of data
and directing all read and writes to the backup memory device
(106).
[0030] The method of FIG. 3 includes switching (308), by the memory
backup controller (102), a designation of the backup memory device
(106) from backup usage to active usage. Switching (308) the
designation of the backup memory device (106) may be carried out by
setting one or more bits to indicate the backup memory device (106)
is to receive future blocks of data to be written and setting one
or more bits to indicate that the backup memory device (106) is to
be used to retrieve data requested via an expansion bus.
[0031] The method of FIG. 3 also includes switching (310), by the
memory backup controller (102), a designation of the active memory
device (104) from active usage to backup usage. Switching (310) the
designation of the active memory device (104) from active usage to
backup usage may be carried out by setting one or more bits to
indicate the active memory device (104) is to not receive future
blocks of data to be written and setting one or more bits to
indicate that the active memory device (104) is not to be used to
retrieve data requested via an expansion bus.
[0032] The method of FIG. 3 includes receiving (312), by the memory
backup controller (102), additional blocks of computer data (314)
from the random access memory (168). Receiving (312) the additional
blocks of computer data (314) from the random access memory (168)
may be carried out by establishing a connection with an expansion
bus via an interface and receiving data over an expansion bus
[0033] The method of FIG. 3 also includes responsive to the
designations of the active memory device (104) and the backup
memory device (106), storing (316), by the memory backup controller
(102), the additional blocks of computer data (314) on a memory
device designated as being in active usage. Storing (316) the
additional blocks of computer data (314) on a memory device
designated as being in active usage may be carried out by
determining which memory device (318) is in active usage,
establishing a connection with the identified memory device (318)
in active usage, and routing the data to the identified memory
device (318) in active usage.
[0034] Exemplary embodiments of the present invention are described
largely in the context of a fully functional computer system for
backup memory administration. Readers of skill in the art will
recognize, however, that the present invention also may be embodied
in a computer program product disposed upon computer readable
storage media for use with any suitable data processing system.
Such computer readable storage media may be any storage medium for
machine-readable information, including magnetic media, optical
media, or other suitable media. Examples of such media include
magnetic disks in hard drives or diskettes, compact disks for
optical drives, magnetic tape, and others as will occur to those of
skill in the art. Persons skilled in the art will immediately
recognize that any computer system having suitable programming
means will be capable of executing the steps of the method of the
invention as embodied in a computer program product. Persons
skilled in the art will recognize also that, although some of the
exemplary embodiments described in this specification are oriented
to software installed and executing on computer hardware,
nevertheless, alternative embodiments implemented as firmware or as
hardware are well within the scope of the present invention.
[0035] As will be appreciated by one skilled in the art, aspects of
the present invention may be embodied as a system, method or
computer program product. Accordingly, aspects of the present
invention may take the form of an entirely hardware embodiment, an
entirely software embodiment (including firmware, resident
software, micro-code, etc.) or an embodiment combining software and
hardware aspects that may all generally be referred to herein as a
"circuit," "module" or "system." Furthermore, aspects of the
present invention may take the form of a computer program product
embodied in one or more computer readable medium(s) having computer
readable program code embodied thereon.
[0036] Any combination of one or more computer readable medium(s)
may be utilized. The computer readable medium may be a computer
readable signal medium or a computer readable storage medium. A
computer readable storage medium may be, for example, but not
limited to, an electronic, magnetic, optical, electromagnetic,
infrared, or semiconductor system, apparatus, or device, or any
suitable combination of the foregoing. More specific examples (a
non-exhaustive list) of the computer readable storage medium would
include the following: an electrical connection having one or more
wires, 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), an optical fiber, a
portable compact disc read-only memory (CD-ROM), an optical storage
device, a magnetic storage device, or any suitable combination of
the foregoing. In the context of this document, a computer readable
storage medium may be any tangible medium that can contain, or
store a program for use by or in connection with an instruction
execution system, apparatus, or device.
[0037] A computer readable signal medium may include a propagated
data signal with computer readable program code embodied therein,
for example, in baseband or as part of a carrier wave. Such a
propagated signal may take any of a variety of forms, including,
but not limited to, electro-magnetic, optical, or any suitable
combination thereof. A computer readable signal medium may be any
computer readable medium that is not a computer readable storage
medium and that can communicate, propagate, or transport a program
for use by or in connection with an instruction execution system,
apparatus, or device.
[0038] Program code embodied on a computer readable medium may be
transmitted using any appropriate medium, including but not limited
to wireless, wireline, optical fiber cable, RF, etc., or any
suitable combination of the foregoing.
[0039] Computer program code for carrying out operations for
aspects of the present invention may be written in any combination
of one or more programming languages, including an object oriented
programming language such as Java, Smalltalk, C++ or the like and
conventional procedural programming languages, such as the "C"
programming language or similar programming languages. The program
code 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).
[0040] Aspects of the present invention are described below 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 program
instructions. These computer 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.
[0041] These computer program instructions may also be stored in a
computer readable medium that can direct a computer, other
programmable data processing apparatus, or other devices to
function in a particular manner, such that the instructions stored
in the computer readable medium produce an article of manufacture
including instructions which implement the function/act specified
in the flowchart and/or block diagram block or blocks.
[0042] The computer program instructions may also be loaded onto a
computer, other programmable data processing apparatus, or other
devices to cause a series of operational steps to be performed on
the computer, other programmable apparatus or other devices to
produce a computer implemented process such that the instructions
which execute on the computer or other programmable apparatus
provide processes for implementing the functions/acts specified in
the flowchart and/or block diagram block or blocks.
[0043] 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 of the present invention. In this
regard, each block in the flowchart or block diagrams may represent
a module, segment, or portion of code, which comprises one or more
executable instructions for implementing the specified logical
function(s). It should also be noted that, 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 combinations of special purpose hardware and computer
instructions.
[0044] It will be understood from the foregoing description that
modifications and changes may be made in various embodiments of the
present invention without departing from its true spirit. The
descriptions in this specification are for purposes of illustration
only and are not to be construed in a limiting sense. The scope of
the present invention is limited only by the language of the
following claims.
* * * * *