Functions

Function to set cache segments

This function allows you to partition cache memory into cache segments and assign logical disks to be used for tenants (business operations) to them. NEC Storage Manager client can be used to perform these operations.

Defining or deleting cache segments

Define or delete cache segments. Or, a cache segment can be reserved as a free space.

Defining size of cache segments

Define or change sizes of cache memory to be allocated to cache segments. Sizes can be defined by either of two policies; allocate fixed capacity; or allocate variable capacity by setting upper and lower limits.

Setting nickname

Set nicknames of your choice to cache segments to facilitate management of cache segments.

Assigning logical disks

Assign logical disks to cache segments on an operation basis and logical disk basis.

Function to display cache segment status

This function displays configuration and status of cache segments. NEC Storage Manager client or command line (iSMview command) can be used.

Displaying usage status

Display whether cache partitioning function is enabled or disabled.

Displaying configuration status

Display nicknames, configured capacity and allocated capacity.

Displaying status of logical disk assignment

Display cache segments and a list of logical disks assigned to the cache segments.

Function to monitor performance

NEC Storage PerformanceMonitor Suite can be used to monitor and analyze workloads on cache segments and it allows you to tune optimal allocation of cache capacity.

Monitoring workloads

Detect and report unexpected high workloads by setting threshold to cache segment performance data.

Post-analysis

Perform analysis with a long-term vision by using the accumulated cache segment performance data as a reference.

Using SSD (Solid State Drive) as L2 cache (NEC Storage PerforCache)

Dividing the cache memory reduces the capacity of each cache memory.
Therefore, cache hit misses, that is, HDD (Hard Disk Drive) access may increase.
In that case, if SSD is used as the L2 cache, access to the HDD is suppressed  and the degradation of the response performance of the disk array is resolved.