Managing a datalog space of a data cache
Embodiments of the present disclosure relate to a method and device and computer readable medium for storage management. The method comprises determining a queuing condition of I/O requests of a cache of a first file system in a storage, the cache including at least one flash block. The method further includes determining a load condition of the cache based on the queuing condition of the I/O requests. Moreover, the method further includes in response to determining that the cache is in a busy status, allocating to the cache at least one additional flash block from a second file system in the storage, the second file system being different from the first file system.
1. A method of storage management, comprising:
determining a queuing condition of I/O requests of a cache of a first file system in a storage, the cache including at least one flash block;
determining a load condition of the cache based on the queuing condition of the I/O requests;
in response to determining that the cache is in a busy status, allocating to the cache at least one additional flash block from a second file system in the storage, the second file system being different from the first file system;
in response to determining, based on the queuing condition of the I/O requests, that the cache is in an idle status, determining whether the cache includes unused flash blocks; and
in response to the cache including the unused flash blocks, removing at least one of the unused flash blocks from the cache.
2. The method according to claim 1 , wherein determining the load condition of the cache comprises:
in response to the number of the I/O requests queued for the cache reaching a first threshold number, determining that the cache is in the busy status.
3. The method according to claim 1 , wherein determining the load condition of the cache comprises:
in response to the number of I/O requests queued for the cache reaching a second threshold number for a first period of time that exceeds a predetermined length, determining that the cache is in the busy status.
4. The method according to claim 1 , wherein the at least one flash block includes N flash blocks, and allocating the at least one additional flash block to the cache comprises:
allocating M additional flash blocks to the cache, M and N being natural numbers and M being a multiple of N.
5. The method according to claim 1 , wherein determining the load condition of the cache comprises:
in response to absence of I/O requests queued for the cache for a second period of time, determining that the cache is in the idle status.
6. The method according to claim 1 , wherein determining the load condition of the cache comprises:
in response to the number of the I/O requests completed for the cache for a third period of time failing to reach a third threshold number, determining that the cache is in the idle status.
7. The method according to claim 1 , wherein the at least one flash block includes a plurality of flash blocks, the method further comprising:
in response to determining that the number of unused flash blocks in the plurality of flash blocks exceeds a predetermined number, removing the predetermined number of unused flash blocks from the cache.
8. The method according to claim 1 , wherein removing at least one of the unused flash blocks from the cache includes:
re-allocating an unused flash block from the cache of the first file system to a different cache, the different cache belonging to a file system that is different from the first file system.
9. The method according to claim 8 wherein the file system that is different from the first file system is a particular file system currently having the busy status; and
wherein re-allocating the unused flash block includes:
removing the unused flash block from a back of the cache and allocating the unused flash block to the particular file system currently having the busy status.
10. A device for storage management, comprising:
at least one processing circuit; and
at least one memory coupled to the at least one processing circuit and storing instructions executable by the at least one processing circuit, the instructions, when executed by the at least one processing circuit, causing the device to perform acts including:
determining a queuing condition of I/O requests of a cache of a first file system in a storage, the cache including at least one flash block;
determining a load condition of the cache based on the queuing condition of the I/O requests;
in response to determining that the cache is in a busy status, allocating to the cache at least one additional flash block from a second file system in the storage, the second file system being different from the first file system;
in response to determining, based on the queuing condition of the I/O requests, that the cache is in an idle status, determining whether the cache includes unused flash blocks; and
in response to the cache including the unused flash blocks, removing at least one of the unused flash block from the cache.
11. The device according to claim 10 , wherein determining the load condition of the cache comprises:
in response to the number of the I/O requests queued for the cache reaching a first threshold number, determining that the cache is in the busy status.
12. The device according to claim 10 , wherein determining the load condition of the cache comprises:
in response to the number of I/O requests queued for the cache reaching a second threshold number for a first period of time that exceeds a predetermined length, determining that the cache is in the busy status.
13. The device according to claim 10 , wherein the at least one flash block includes N flash blocks, and allocating the at least one additional flash block to the cache comprises:
allocating M additional flash blocks to the cache, M and N being natural numbers and M being a multiple of N.
14. The device according to claim 10 , wherein determining the load condition of the cache comprises:
in response to absence of I/O requests queued for the cache for a second period of time, determining that the cache is in the idle status.
15. The device according to claim 10 , wherein determining the load condition of the cache comprises:
in response to the number of the I/O requests completed for the cache for a third period of time failing to reach a third threshold number, determining that the cache is in the idle status.
16. The device according to claim 10 , wherein the at least one flash block includes a plurality of flash blocks, the acts further including:
in response to determining that the number of unused flash blocks of the plurality of flash blocks exceeds a predetermined number, removing the predetermined number of unused flash blocks from the cache.
17. A computer readable storage medium having computer readable program instructions stored thereon, the computer readable program instructions, when executed by a processing circuit unit, causing the processing circuit to perform the steps of:
determining a queuing condition of I/O requests of a cache of a first file system in a storage, the cache including at least one flash block;
determining a load condition of the cache based on the queuing condition of the I/O requests;
in response to determining that the cache is in a busy status, allocating to the cache at least one additional flash block from a second file system in the storage, the second file system being different from the first file system;
in response to determining, based on the queuing condition of the I/O requests, that the cache is in an idle status, determining whether the cache includes unused flash blocks; and
in response to the cache including the unused flash blocks, removing at least one of the unused flash blocks from the cache.
18. The computer readable storage medium of claim 17 , wherein determining the load condition of the cache comprises:
in response to the number of the I/O requests queued for the cache reaching a first threshold number, determining that the cache is in the busy status.
19. The computer readable storage medium according to claim 17 , wherein determining the load condition of the cache comprises:
in response to the number of I/O requests queued for the cache reaching a second threshold number for a first period of time that exceeds a predetermined length, determining that the cache is in the busy status.
20. The computer readable storage medium according to claim 17 , wherein the at least one flash block includes N flash blocks, and allocating the at least one additional flash block to the cache comprises:
allocating M additional flash blocks to the cache, M and N being natural numbers and M being a multiple of N.