When I put my database under a load test (basically just a basic write and basic read from our app), and run show processlist;
in the middle of it, there is always 131 rows in the set and that's it. I'm running a master slave with 16GB of memory on each on a Joyent Percona instances which is based on Solaris 10. They are configured to each use up to 8GB memory and 5000 max concurrent connection. What could be limiting it to 131?
Mysql – Show processlist / Max concurrent connections seem to max out at 131
concurrencymax-connectionsMySQL
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Best Answer
I once wrote about the kind of things to tweak when seeing output from mysqltuner.pl : Understanding mysqltuner Recomendations w/ Unused Catalogs
Here is the kind of output it generates
From the output, you should keep watch on
Maximum possible memory usage: 402.6M (6% of installed RAM)
Total buffers: 322.0M global + 5.4M per thread (15 max threads)
Highest usage of available connections
If you see the
per thread
value, remember that is is made up ofadded together and then multiplied by the
max_connections
. That can have a bearing out how much memory can be consumed. Since you are hitting the 131 connection limit, perhaps you can multiple theper thread
value by 131. Once you do, look back at how much RAM is consumed. Remember to reason on the fact that you are in a VM environment. From the OS point of view, you could be swapping or be the victim of process "steal" as seen in%st
intop
.Keep in mind that RAM becomes a premium commodity in a VM, and MySQL will adhere to it without question.
I hope this wild brainstorming of mine helps ...