eG Monitoring
 

Measures reported by ESSearchTest

This test auto-discovers the indices in the Elasticsearch cluster, and reports the time taken to process the search requests, using which administrators can initiate remedial measure if the slowness is detected. This test also reports the number of evictions performed in the query cache and the field data cache and the size of the query cache and field data cache. Using these revelations, admininistrators can detect the inconsistencies in the sizing of the cache in each index.

Output of the test: One set of results for each index in the target Elasticsearch cluster.

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
Query_Latency Indicates the average time taken for processing the search requests in this index. Milliseconds This value is calculated using the following formula:

Query latency=Total time taken for processing all queries/Total number of queries received

The value of this measure is desired to be low. A high value indicates that the index is taking too long to process the queries which may lead to processing bottleneck condition.
Query_Rate Indicates the rate at which the search queries were processed in this index. Queries/sec This measure helps administrator to figure out how well/badly the search requests are performed in each index. A very high value for this measure indicates that the index is imposed with many search requests.
Query_Cache_Eviction Indicates the number of cache evictions performed while processing the search queries in this index. Number The query cache is responsible for caching the results of queries. When the cache is full, the least recently used data is evicted to make way for new data. A high value of this measure indicates that the query cache is full or the cache size is insufficient for the node. This way, the administrators are alerted to inadequate size of the cache and are further enabled to increase the size of the cache, if needed.
Query_Cache_Size Indicates the current size of the query cache of this index. MB  
Field_Data_Cache_Eviction Indicates the number of evictions performed in the field data cache while processing the search queries in this index. Number The field data cache is used mainly when sorting on or computing aggregations on a field, and loads all the field values to memory in order to provide fast document based access to computed values. Compare the value of this mesaure across the indices to identify the index in which the maximum number of evictions were performed in the field data cache.
Field_Data_Cache_Size Indicates the current size of the filed data cache of this index. MB