Why does counter slowly?

memcached<0.76.0>: 2016-08-29T17:20:12.185119+08:00 WARNING 61: Slow INCREMENT operation on connection (192.168.103.56:2784 => 192.168.102.124:11210): 4466 ms
i just increment a integer,why does it so slowly?

where does that warning come from? the server logs?

it comes from babysitter.log

i rebalance the bucket it does return to normal

Which version of Couchbase Server are you using? Are you using full eviction on the bucket in question?

this “4.1.0-5005 Enterprise Edition (build-5005)”

yes i enable the " full eviction" , does there has hole?

Unfortunately there is a known issue with full eviction and counters: MB-17231. This is fixed in Couchbase Server 4.1.1 (and 4.1.2) and will be fixed in Couchbase Server 4.5.1.

In this case the counter hangs until something else like another operation or compaction operates on the document in question.

Upgrading to Couchbase 4.1.2 should resolve the issue.

i upgrading to Couchbase 4.5,turn on the ‘full eviction’,counter was still thrown ‘timeout exception’,i use client-2.3.1