Performance metrics for Hitachi VSP storage systems
Monitor the performance metrics that are collected for storage systems.
The following performance metrics are available for Hitachi VSP storage systems.
A performance metric might apply to one or more storage resources. To check which resources the performance metric applies to, see the tips.
Volume metrics
Volume performance metrics are divided into the following categories:
Tip: You can view the volume metrics in Key volume
metrics for the following resources:
- Volumes
- Pools
- Storage systems
| Metric | Description |
|---|---|
| Overall I/O Rate (Read) | The average number of read operations per second. This value includes both sequential and nonsequential read operations. |
| Overall I/O Rate (Write) | The average number of write operations per second. This value includes both sequential and nonsequential write operations. |
| Overall I/O Rate (Total) | The average number of read operations and write operations per second. This value includes both sequential and nonsequential operations. |
| Data Rate (Read) | The average number of MiBs per second that are transferred for read operations. |
| Data Rate (Write) | The average number of MiBs per second that are transferred for write operations. |
| Data Rate (Total) | The average number of MiB per second that are transferred for read operations and write operations. |
| Response Time (Read) | The average number of milliseconds to complete a read operation. |
| Response Time (Write) | The average number of milliseconds to complete a write operation. |
| Response Time (Overall) | The average number of milliseconds to complete an I/O operation. This value includes both read and write operations. |
| Transfer Size (Read) | The average number of KiB that are transferred per read operation. |
| Transfer Size (Write) | The average number of KiB that are transferred per write operation. |
| Transfer Size (Overall) | The average number of KiB that are transferred per I/O operation. This value includes both read and write operations. |
Tip: You can view the volume metrics in Cache hit
metrics for the following resources:
- Volumes
- Pools
- Storage systems
| Metric | Description |
|---|---|
| Overall I/O Cache Hits (Read) % | 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 I/O Cache Hits (Write) % | 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. |
Port metrics
You can view the metrics in Key port metrics for ports and storage systems.
| Metric | Description |
|---|---|
| I/O Rate (Total) | The average number of read operations and write operations per second. This value includes both sequential and nonsequential operations. |
| Data Rate (Total) | The average rate at which data is transferred through the port. The rate is measured in MiB per second and includes both send and receive operations. |
| Response Time (Overall) | The average rate at which data is transferred through the port. The rate is measured in MiB per second and includes both send and receive operations. |
| Transfer Size (Overall) | The average number of KiB that are transferred per I/O operation. This value includes both send and receive operations. |
Node metrics
You can view the metrics in Key node metrics for storage systems.
| Metric | Description |
|---|---|
| System CPU | The average percentage of time that the processors on nodes are busy doing system I/O tasks. |