Are both instances running the same MySQL version and release? Are they MASTER and SLAVE, actively replicating? Are the InnoDB configurations currently running on both servers the same?
-- *WB* 2014-09-06 6:00 GMT-03:00 Ajay Garg <ajaygargn...@gmail.com>: > Sorry, forgot to specify the engine. > The table runs on InnoDB backend. > > Also, changed the subject to be more specific. > > > On Sat, Sep 6, 2014 at 2:26 PM, Ajay Garg <ajaygargn...@gmail.com> wrote: > > Hi all. > > > > > > We are facing a very strange scenario. > > > > We have two mysql-instances running on the same machine, and they had > > been running functionally fine since about 6 years or so (catering to > > millions of records per day). > > > > However, since last few days, we were experiencing some elongated > > slowness on both the instances. > > So, we decided to "OPTIMIZE TABLE slow_table" on both the instances. > > > > We first ran the command on one instance. > > That speeded up things massively (select count(*) that was earlier > > taking 45 minutes was now running in less than 3 minutes). > > > > > > We then ran the command on the second instance. However, that seemed > > to have no effect. > > We ran the command again (on the same instance); again it had no effect. > > > > > > > > What could be the reason of this strange behavior? > > Both the instances run under fairly the same load, and both instances > > are mounted on the same partition (obviously, all the directories are > > different). > > > > > > Hoping for some light on this strange issue. > > > > > > > > Thanks and Regards, > > Ajay > > > > -- > Regards, > Ajay > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/mysql > >
