Performance metrics for storage host connections on an XIV

You can include performance metrics for volumes, caches, and for other data for storage host connections on an XIV in performance reports.

Volume data

You can create performance reports that include the following information:

Overall Read I/O Rate (ops/s): The average number of read operations per second. This value includes both sequential and nonsequential read operations.
Overall Write I/O Rate (ops/s): The average number of write operations per second. This value includes both sequential and nonsequential write operations.
Total Overall I/O Rate (ops/s): The average number of read operations and write operations per second. This value includes both sequential and nonsequential operations.
Read Data Rate (MiB/s): The average number of MiBs per second that are transferred for read operations.
Write Data Rate (MiB/s): The average number of MiBs per second that are transferred for write operations.
Total Data Rate (MiB/s): The average number of MiB per second that are transferred for read operations and write operations.
Read Response Time (ms/op): The average number of milliseconds to complete a read operation.
Write Response Time (ms/op): The average number of milliseconds to complete a write operation.
Overall Response Time (ms/op): The average number of milliseconds to complete an I/O operation. This value includes both read and write operations.
Read Transfer Size (KiB/op): The average number of KiB that are transferred per read operation.
Write Transfer Size (KiB/op): The average number of KiB that are transferred per write operation.
Overall Transfer Size (KiB/op): The average number of KiB that are transferred per I/O operation. This value includes both read and write operations.

Cache data

You can create performance reports that include the following information:

Overall Read Cache Hit Percentage: The percentage of all read operations that find data in the cache. This value includes both sequential and random read operations, and read operations in the volume cache and volume copy cache where applicable.; You can use this value to understand throughput or response times. Low cache-hit percentages can increase response times because in the event of a cache miss, the data must be read from the back-end storage resources.
Overall Write Cache Hit Percentage: The percentage of all write operations that are handled in the cache. This value includes both sequential and random write operations, and write operations in the volume cache and volume copy cache where applicable.
Total Overall Cache Hit Percentage: The percentage of all read operations and write operations that are handled in the cache. This value includes both sequential and random read and write operations, and read and write operations in the volume cache and volume copy cache where applicable.; You can use this value to understand throughput or response times. Low cache-hit percentages can increase response times because a cache miss requires access to the back-end storage resources.
Read Data Cache Hit Percentage: The percentage of all read data that is read from the cache.
Write Data Cache Hit Percentage: The percentage of all write data that is written to cache slots that are marked as modified.
Overall Data Cache Hit Percentage: The percentage of all data that is handled in the cache. This value includes read data that is read from the cache and write data that is written to cache slots that are marked as modified.
Read Cache Hit Response Time (ms/op): The average number of milliseconds to complete a read-cache hit operation.
Write Cache Hit Response Time (ms/op): The average number of milliseconds to complete a write-cache hit operation.
Overall Cache Hit Response Time (ms/op): The average number of milliseconds to complete a cache hit operation. This value includes the times for both read-cache hit and write-cache hit operations.
Read Cache Miss Response Time (ms/op): The average number of milliseconds to complete a read-cache miss operation.
Write Cache Miss Response Time (ms/op): The average number of milliseconds to complete a write-cache miss operation.
Overall Cache Miss Response Time (ms/op): The average number of milliseconds to complete a cache miss operation. This value includes the times for both read-cache miss and write-cache miss operations.

Other data

You can create performance reports that include the following information:

Small Transfers I/O Percentage: The percentage of I/O operations with a small data transfer size. A small data transfer has a size that is less than or equal to 8 KiB.
Medium Transfers I/O Percentage: The percentage of I/O operations with a medium data transfer size. A medium data transfer has a size that is greater than 8 KiB and less than or equal to 64 KiB.
Large Transfers I/O Percentage: The percentage of I/O operations with a large data transfer size. A large data transfer has a size that is greater than 64 KiB and less than or equal to 512 KiB.
Very Large Transfers I/O Percentage: The percentage of I/O operations with a data transfer size that is greater than 512 KiB.
Small Transfers Data Percentage: The percentage of data that is transferred as a result of I/O operations with a small data transfer size. A small data transfer has a size that is less than or equal to 8 KiB.
Medium Transfers Data Percentage: The percentage of data that is transferred as a result of I/O operations with a medium data transfer size. A medium data transfer has a size that is greater than 8 KiB and less than or equal to 64 KiB.
Large Transfers Data Percentage: The percentage of data that is transferred as a result of I/O operations with a large data transfer size. A large data transfer has a size that is greater than 64 KiB and less than or equal to 512 KiB.
Very Large Transfers Data Percentage: The percentage of data that is transferred as a result of I/O operations with a data transfer size that is greater than 512 KiB.
Small Transfers Response Time (ms/op): The average number of milliseconds to complete an I/O operation that has a small data transfer size. A small data transfer has a size that is less than or equal to 8 KiB.
Medium Transfers Response Time (ms/op): The average number of milliseconds to complete an I/O operation that has a medium data transfer size. A medium data transfer has a size that is greater than 8 KiB and less than or equal to 64 KiB.
Large Transfers Response Time (ms/op): The average number of milliseconds to complete an I/O operation that has a large data transfer size. A large data transfer has a size that is greater than 64 KiB and less than or equal to 512 KiB.
Very Large Transfers Response Time (ms/op): The average number of milliseconds to complete an I/O operation with a data transfer size that is greater than 512 KiB.