Is there any reason that match all queries would be impacted significantly by index size?
It seems that in the absence of any sort, query or other mechanism requiring scoring it should just be a matter of fetching the first document from a shard. In practice that does not seem to be the case. On a cluster with more than sufficient ram, registering no noticeable disk io, the match_all query is reporting took times of 400-500ms. The match_all query seems to use a significant amount of CPU, and when attempted concurrently drives the CPU to 100% with only 30 concurrent requests. This also puts a significant level of context switching on the nodes of the cluster. The cluster in question is described in this post, though it now has 4 such nodes and performance has not improved. Sairam has posted a few times about it but each thread has just ended with no direction. https://groups.google.com/d/msg/elasticsearch/P1o_4bVvECA/lDbCp_rCH_YJ We were able to make some tweaks to the query with filters and sorts, such that it is now significantly faster than the match_all query, took times as low as 8 where previously it was 800. Is there something that I am missing? -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/0e88051f-b3b1-44d1-87e5-26245b4e3ab3%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
