During performance testing of our application I found that under extreme loads one problem that can occur is the occasional mysql connection error (i.e. at this stage I don't believe it is fair to call it a bug). Eventually the application will get blocked by mysql. I can extend the
SET GLOBAL max_connect_errors=10000; (currently 10) but assuming 100% mysql uptime over a very very long time would this problem eventually reoccur?
This is the "blocked-host" feature of mysql:
Without proactive intervention will the connection error count ever flush or otherwise decline?
I have found conflicting information, Percona recommend a very high limit ("around 1000000 is good") implying no. But elsewhere in the documentation states only successive errors are counted meaning yes, a single successful connection will flush the error count.
If too many of these occur successively from a given host without a successful connection, the server blocks further connections from that host. The max_connect_errors system variable determines the number of permitted errors before blocking occurs
Is anyone running mysql 5.6.5 where host_cache is exposed or know definitively?