XIV performance metrics

Metrics data available in the IBM® XIV® Performance dashboard provides health and performance information for the IBM XIV resources.

Different metric types are available for different resource elements, as detailed in tables below.

Table 1. Capacity metrics
Metrics	Description	Relevant IBM XIV resource
Hard (GB)	Hard size (actual physical capacity) of the resource	Volume, Pool, Array
Soft (GB)	Soft size (maximum size of capacity seen by the hosts) of the resource	Volume, Pool, Array
Free Hard (GB)	Free hard size of the array	Array
Free Soft (GB)	Free soft size of the array	Array
Utilization Hard (%)	Utilization ratio of the hard capacity	Volume, Array
Utilization Soft (%)	Utilization ratio of the soft capacity	Volume, Array
Over Provisioning Ratio (%)	The ratio between virtual capacity and real capacity of the pool	Pool

Table 2. Health metrics
Metrics	Description	Relevant IBM XIV resource
Connected	Connection status of the resource	Host, Host FC Initiator, Host iSCSI Initiator
Status	Health status of the module	Module
Requires Service	Heath status of the disk. The REPLACE value indicates disk failure.	Disk
Online	Connection status of the resource	Module FC Port, Module iSCSI Port

Table 3. Counter metrics
Metrics	Description	Relevant IBM XIV resource
Hosts Count	Total number of hosts connected to the array	Array
Mirror Relations Count	Total number of mirror relations (master or slave) existing in the array
Pools Count	Total number of pools existing in the array
Snapshots Count	Total number of snapshots existing in the array
Volumes and Snapshots Count	Total number of volumes and snapshots existing in the array
Volumes Count	Total number of volumes existing in the array

Table 4. Perfromance metrics
Metrics	Description	Relevant IBM XIV resource
Total IOPS	Total number of IOPS performed by the resource	Array, Host FC Initiator, Host iSCSI Initiator, Module FC Port, Module iSCSI Port
Total Read IOPS	Total number of read IOPS performed by the resource
Total Write IOPS	Total number of write IOPS performed by the resource
Read Hit Large IOPS	Number of IOPS for 64–512 KB packets read from cache
Read Hit Medium IOPS	Number of IOPS for 8–64 KB packets read from cache
Read Hit Small IOPS	Number of IOPS for 0–8 KB packets read from cache
Read Hit Very Large IOPS	Number of IOPS for over 512 KB packets read from cache
Read Miss Large IOPS	Number of IOPS for 64–512 KB packets read from disk
Read Miss Medium IOPS	Number of IOPS for 8–64 KB packets read from disk
Read Miss Small IOPS	Number of IOPS for 0–8 KB packets read from disk
Read Miss Very Large IOPS	Number of IOPS for over 512 KB packets read from disk
Write Hit Large IOPS	Number of IOPS for 64–512 KB packets written to cache
Write Hit Medium IOPS	Number of IOPS for 8–64 KB packets written to cache
Write Hit Small IOPS	Number of IOPS for 0–8 KB packets written to cache
Write Hit Very Large IOPS	Number of IOPS for over 512 KB packets written to cache
Write Miss Large IOPS	Number of IOPS for 64–512 KB packets written to disk
Write Miss Medium IOPS	Number of IOPS for 8–64 KB packets written to disk
Write Miss Small IOPS	Number of IOPS for 0–8 KB packets written to disk
Write Miss Very Large IOPS	Number of IOPS for over 512 KB packets written to disk
Average Latency	Average response time
Average Write Latency	Average response time of a write operation
Average Read Latency	Average response time of a read operation
Read Hit Large Latency	Response time of cache read operations for 64–512 KB packets
Read Hit Medium Latency	Response time of cache read operations for 8–64 KB packets
Read Hit Small Latency	Response time of cache read operations for 0–8 KB packets
Read Hit Very Large Latency	Response time of cache read operations for over 512 KB packets
Read Memory Hit Large Latency	Response time of DRAM cache read operations for 64–512 KB packets	Array
Read Memory Hit Medium Latency	Response time of DRAM cache read operations for 8–64 KB packets
Read Memory Hit Small Latency	Response time of DRAM cache read operations for 0–8 KB packets
Read Memory Hit Very Large Latency	Response time of DRAM cache read operations for over 512 KB packets
Read Miss Large Latency	Response time of disk read operations for 64–512 KB packets	Array, Host FC Initiator, Host iSCSI Initiator, Module FC Port, Module iSCSI Port
Read Miss Medium Latency	Response time of disk read operations for 8–64 KB packets
Read Miss Small Latency	Response time of disk read operations for 0–8 KB packets
Read Miss Very Large Latency	Response time of disk read operations for over 512 KB packets
Write Hit Large Latency	Response time of cache write operations for 64–512 KB packets
Write Hit Medium Latency	Response time of cache write operations for 8–64 KB packets
Write Hit Small Latency	Response time of cache write operations for 0–8 KB packets
Write Hit Very Large Latency	Response time of cache write operations for over 512 KB packets
Write Miss Large Latency	Response time of disk write operations for 64–512 KB packets
Write Miss Medium Latency	Response time of disk write operations for 8–64 KB packets
Write Miss Small Latency	Response time of disk write operations for 0–8 KB packets
Write Miss Very Large Latency	Response time of disk write operations for over 512 KB packets
Total Throughput	Total bandwidth
Total Read Throughput	Total bandwidth used by read operations
Total Write Throughput	Total bandwidth used by write operations
Read Hit Large Throughput	Bandwidth used by cache read operations for 64–512 KB packets
Read Hit Medium Throughput	Bandwidth used by cache read operations for 8–64 KB packets
Read Hit Small Throughput	Bandwidth used by cache read operations for 0–8 KB packets
Read Hit Very Large Throughput	Bandwidth used by cache read operations for over 512 KB packets
Read Memory Hit Large Throughput	Bandwidth used by DRAM cache read operations for 64–512 KB packets	Array
Read Memory Hit Medium Throughput	Bandwidth used by DRAM cache read operations for 8–64 KB packets
Read Memory Hit Small Throughput	Bandwidth used by DRAM cache read operations for 0–8 KB packets
Read Memory Hit Very Large Throughput	Bandwidth used by DRAM cache read operations for over 512 KB packets
Read Miss Large Throughput	Bandwidth used by disk read operations for 64–512 KB packets	Array, Host FC Initiator, Host iSCSI Initiator, Module FC Port, Module iSCSI Port
Read Miss Medium Throughput	Bandwidth used by disk read operations for 8–64 KB packets
Read Miss Small Throughput	Bandwidth used by disk read operations for 0–8 KB packets
Read Miss Very Large Throughput	Bandwidth used by disk read operations for over 512 KB packets
Write Hit Large Throughput	Bandwidth used by cache write operations for 64–512 KB packets
Write Hit Medium Throughput	Bandwidth used by cache write operations for 8–64 KB packets
Write Hit Small Throughput	Bandwidth used by cache write operations for 0–8 KB packets
Write Hit Very Large Throughput	Bandwidth used by cache write operations for over 512 KB packets
Write Miss Large Throughput	Bandwidth used by disk write operations for 64–512 KB packets
Write Miss Medium Throughput	Bandwidth used by disk write operations for 8–64 KB packets
Write Miss Small Throughput	Bandwidth used by disk write operations for 0–8 KB packets
Write Miss Very Large Throughput	Bandwidth used by disk write operations for over 512 KB packets
Aborts	Total number of I/Os aborted during the current mirroring operation
Failures	Total number of I/Os failed during the current mirroring operation