Hi Sergei, On Sat, Mar 01, 2014 at 07:47:07PM +0100, Sergei Golubchik wrote:

Hi, Sergey!

On Feb 27, Sergey Vojtovich wrote:

...

At lp:maria/10.0

------------------------------------------------------------ revno: 4011 revision-id: svoj@mariadb.org-20140227141521-fgj5b0h3qbijyojh parent: svoj@mariadb.org-20140220072533-l3au3y7mrsyclfpb committer: Sergey Vojtovich branch nick: 10.0 timestamp: Thu 2014-02-27 18:15:21 +0400 message: MDEV-5755 - Scalability: let LOCK_open and THR_LOCK::mutex be normal mutexes

Normal mutexes scale better than adaptive at high thread count. At low thread count they behave similarly.

To summarize Axel results: at low concurency normal can be ~1% slower. at high concurrency r/o - normal are up to 25% faster. at high concurrency r/w - normal are up to 10% slower.

That last result bothers me a litte. Indeed. I'll check with Axel about it. Thanks for pointing it out!

Thanks, Sergey