eG Monitoring
 

Measures reported by CouchDBCmpctTest

Compaction operation is the way to reduce disk space usage by removing unused and old data from database or view index files. This operation is very similar to the vacuum (SQLite ex.). During compaction, the target CouchDB creates new file with the .compact extension and transfers only actual data into. Because of this, CouchDB checks first for the available disk space - it should be twice greater than the compacted file's data. When all actual data is successfully transferred to the compacted file, CouchDB replaces the target with the compacted file.

This test monitors the target CouchDB server and reports the number of compactions running on the server. In addition, this test also reveals the number of compactions running for a long time and also reports the running time of compaction greater than the configured running time. Using this test, administrators can be alerted to irregularities in compaction process if any, and rectify them at a faster pace.

Outputs of the test : One set of results for the target Apache CouchDB Server.

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
compact_Count Indicates the number of compactions running on the server. Number  
long_Running_Compactions Indicates the number of compactions running on the target server for a long time Number Ideally, the value of this measure should be 0. A non-zero value is indicative of compaction issues.

Use the detailed diagnosis of this measure to figure out the process Id, duration and started time of compaction process.
maximum_Compact_Time Indicates the running time of compaction greater than the configured running time. Seconds A low value is desired for this measure.