摘要:
Systems and methods for allocating task control blocks in an information storage and retrieval system are disclosed. Task control blocks for new writes and reads are allocated by the cache code after a determination of the number of task control blocks already allocated for other tasks.
摘要:
Embodiments for facilitating data transfer between a nonvolatile storage (NVS) write cache and a pool of target storage devices are provided. Each target storage device in the pool of target storage devices is determined as one of a hard disk drive (HDD) and a solid-state drive (SSD) device, and classified into one of a SSD rank group and a HDD rank group. If no data is received in the NVS write cache for a predetermined time to be written to a target storage device classified in the SSD rank group, a threshold of available space in the NVS write cache is set to allocate at least a majority of the available space to the HDD rank group. Upon receipt of a write request for the SSD rank group, the threshold of the available space is reduced to allocate a greater portion of the available space to the SSD rank group.
摘要:
An I/O enclosure module is provided with one or more I/O enclosures having a plurality of slots for receiving electronic devices. A host adapter is connected a first slot of the I/O enclosure module and is configured to connect a host to the I/O enclosure. A device adapter is connected to a second slot of the I/O enclosure module and is configured to connect a storage device to the I/O enclosure module. A flash cache is connected to a third slot of the I/O enclosure module and includes a flash-based memory configured to cache data associated with data requests handled through the I/O enclosure module. A primary processor complex manages data requests handled through the I/O enclosure module by communicating with the host adapter, device adapter, and flash cache to manage to the data requests.
摘要:
An I/O enclosure module is provided with one or more I/O enclosures having a plurality of slots for receiving electronic devices. A host adapter is connected a first slot of the I/O enclosure module and is configured to connect a host to the I/O enclosure. A device adapter is connected to a second slot of the I/O enclosure module and is configured to connect a storage device to the I/O enclosure module. A flash cache is connected to a third slot of the I/O enclosure module and includes a flash-based memory configured to cache data associated with data requests handled through the I/O enclosure module. A primary processor complex manages data requests handled through the I/O enclosure module by communicating with the host adapter, device adapter, and flash cache to manage to the data requests.
摘要:
A method of dynamic allocation of non-volatile memory in a cache storage subsystem includes constraining a redundant array of independent disks (RAID) 6 array in an unavailable state, the RAID 6 array having been newly created in the subsystem, destaging data from a write cache to a storage medium to free memory space, reserving the freed memory space for allocation to data-persistent storage, allocating the memory space to an adapter in the subsystem as a target for data in the event of a power loss, and changing the RAID 6 array to an available state. A system for dynamic allocation of non-volatile memory in a cache storage subsystem includes a computer processing device which constrains a newly-created redundant array of independent disks (RAID) 6 array in an unavailable state to execute a reconfiguration method.
摘要:
A method of dynamic allocation of non-volatile memory in a cache storage subsystem includes constraining a redundant array of independent disks (RAID) 6 array in an unavailable state, the RAID 6 array having been newly created in the subsystem, destaging data from a write cache to a storage medium to free memory space, reserving the freed memory space for allocation to data-persistent storage, allocating the memory space to an adapter in the subsystem as a target for data in the event of a power loss, and changing the RAID 6 array to an available state. A system for dynamic allocation of non-volatile memory in a cache storage subsystem includes a computer processing device which constrains a newly-created redundant array of independent disks (RAID) 6 array in an unavailable state to execute a reconfiguration method.
摘要:
The population of data to be admitted into secondary data storage cache of a data storage system is controlled by determining heat metrics of data of the data storage system. If candidate data is submitted for admission into the secondary cache, data is selected to tentatively be evicted from the secondary cache; candidate data provided to the secondary data storage cache is rejected if its heat metric is less than the heat metric of the tentatively evicted data; and candidate data submitted for admission to the secondary data storage cache is admitted if its heat metric is equal to or greater than the heat metric of the tentatively evicted data.
摘要:
Provided are a computer program product, system, and method for managing data in a cache system comprising a first cache, a second cache, and a storage system. A determination is made of tracks stored in the storage system to demote from the first cache. A first stride is formed including the determined tracks to demote. A determination is made of a second stride in the second cache in which to include the tracks in the first stride. The tracks from the first stride are added to the second stride in the second cache. A determination is made of tracks in strides in the second cache to demote from the second cache. The determined tracks to demote from the second cache are demoted.
摘要:
Provided are a computer program product, system, and method for managing unmodified tracks maintained in both a first cache and a second cache. The first cache has unmodified tracks in the storage subject to Input/Output (I/O) requests. Unmodified tracks are demoted from the first cache to a second cache. An inclusive list indicates unmodified tracks maintained in both the first cache and a second cache. An exclusive list indicates unmodified tracks maintained in the second cache but not the first cache. The inclusive list and the exclusive list are used to determine whether to promote to the second cache an unmodified track demoted from the first cache.
摘要:
A technique for limiting an amount of write data stored in a cache memory includes determining a usable region of a non-volatile storage (NVS), determining an amount of write data in a current write request for the cache memory, and determining a failure boundary associated with the current write request. A count of the write data associated with the failure boundary is maintained. The current write request for the cache memory is rejected when a sum of the count of the write data associated with the failure boundary and the write data in the current write request exceeds a determined percentage of the usable region of the NVS.