| Measurement |
Description |
Measurement Unit |
Interpretation |
| arcHitRatio |
Indicates the ARC hit ratio during the last measurement period. |
Percent |
A high value is desired for this measure.
|
| avgDataHits |
Indicates the average data hits during the last measurement period. |
Hits/sec |
Data hit occurs when a data block is in the ARC DRAM cache and had returned.
A high value is desired for this measure. A very low value is a cause for concern.
|
| peakDataHits |
Indicates the peak data hit during the last measurement period. |
Hits/sec |
The detailed diagnosis shows when data requests had hit peaks.
|
| avgDataMisses |
Indicates the average data misses during the last measurement period. |
Misses/sec |
Data miss is when a data block is not in the ARC DRAM cache and is read from the L2ARC cache devices (if available and the data is cached on them) or the pool disks.
A high value is desired for this measure. A very low value is a cause for concern.
|
| peakDataMisses |
Indicates the peak data misses during the last measurement period. |
Misses/sec |
The detailed diagnosis shows when data requests had been unsuccessful thus causing degradation in performance.
|
| avgMetaDataHits |
Indicates the average metadata hits during the last measurement period. |
Hits/sec |
The term metadata refers to the “data about data” and is a concept utilized to store the data for all form modifications.
This measure displays the average count of successful metadata requests.
|
| peakMetaDataHits |
Indicates the peak metadata hits during the last measurement period. |
Hits/sec |
The detailed diagnosis shows when and how many metadata requests had been successful.
|
| avgMetaDataMisses |
Indicates the average metadata misses during the last measurement period. |
Misses/sec |
A high value of this measure can cause performance degradation of the system and increases latency.
|
| peakMetaDataMisses |
Indicates the peak metadata misses during the last measurement period. |
Misses/sec |
The detailed diagnosis shows when and how many metadata requests had been unsuccessful.
|
| avgPrefetchedDataHits |
Indicates the average prefetched data hits during the last measurement period. |
Hits/sec |
Prefetching is read-ahead caching. It lets the SP anticipate the data an application will request, so that it can read it from disk into its read cache before the data is needed.
A high value is desired for this measure.
|
| peakPrefetchedDataHits |
Indicates the peak prefetched data hits during the last measurement period. |
Hits/sec |
The detailed diagnosis shows when and how many prefetched data requests had been successful.
|
| avgPrefetchedDataMisses |
Indicates the average prefetched data misses during the last measurement period. |
Misses/sec |
A high value of this measure can cause performance degradation of the system and increases latency.
|
| peakPrefetchedDataMisses |
Indicates the peak prefetched data misses during the last measurement period. |
Misses/sec |
The detailed diagnosis shows when and how many prefetched data requests had been unsuccessful.
|