eG Monitoring

Measures reported by OraZFSARCSStTest The ARC (Adaptive Replacement Cache) size shows the size of the primary filesystem cache, the DRAM based ZFS ARC. The ARC should automatically increase in size to fill most of available DRAM, when enough data be accessed by the current workload to be placed in the cache. The breakdown allows the contents of the ARC to be identified by type. This may also be checked when using cache devices (L2ARC) on systems with limited DRAM, as the ARC can become consumed with L2ARC headers. Using the OraZFSARCSStTest, the administrator can analyze and understand the average ARC data size, header size, and when high utilization had occurred. Outputs of the test: One set of results for the Oracle ZFS Storage System being monitored. The measures made by this test are as follows:
Measurement | Description | Measurement Unit | Interpretation
--- | --- | --- | ---
arcSize | Indicates the current ARC Size. | GB |
avgARCDataSize | Indicates the average ARC data size during the last measurement period. | GB |
peakARCDataSize | Indicates the peak ARC data size during the last measurement period. | GB | Use the detailed diagnosis of this measure to know when cached contents, including filesystem data and filesystem metadata had been highly utilized.
avgARCHeadersSize | Indicates the average ARC headers size during the last measurement period. | GB |
peakARCHeadersSize | Indicates the peak ARC headers size during the last measurement period. | GB | Use the detailed diagnosis of this measure to know when metadata of the ARC had been highly utilized.
avgARCOtherSize | Indicates the average ARC other size during the last measurement period. | GB |
peakARCOtherSize | Indicates the peak ARC other size during the last measurement period. | GB | Use the detailed diagnosis of this measure to know when kernel members other than ARC header and ARC data had been highly utilized.
avgL2ARCHeadersSize | Indicates the average L2ARC headers size during the last measurement period. | GB |
peakL2ARCHeadersSize | Indicates the peak L2ARC headers size during the last measurement period. | GB | Use the detailed diagnosis of this measure to know when L2ARC headers had been highly utilized.