Bin Shi created PHOENIX-5069:
--------------------------------
Summary: Use asynchronous refresh to provide non-blocking Phoenix
Stats Client Cache
Key: PHOENIX-5069
URL: https://issues.apache.org/jira/browse/PHOENIX-5069
Project: Phoenix
Issue Type: Improvement
Reporter: Bin Shi
Attachments: image-2018-12-13-11-16-16-884.png
Below is the high level picture of Phoenix Stats Cache which is based on Google
Guava cache.
!OmCWFETQAAAABJRU5ErkJggg==! The current Phoenix Stats Cache uses TTL based
eviction policy. A cached entry will expire after a given amount of time (900s
by default) passed since the entry's been created. This will lead to cache miss
when Compiler/Optimizer fetches stats from cache at the next time. As you can
see from the above graph, fetching stats from the cache is a blocking operation
— when there is cache miss, it has a round trip over the wire to scan the
SYSTEM.STATS Table and to get the latest stats info, rebuild the cache and
finally return the stats to the Compiler/Optimizer. Whenever there is a cache
miss, this blocking call causes significant performance penalty and see
periodic spikes.
This Jira suggests to use asynchronous refresh mechanism[link
title|http://example.com][link title|http://example.com] to fix this and
provide a non-blocking cache.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
