On Monday 24 July 2006 09:06, Duncan Hill wrote: > On Monday 24 July 2006 09:05, Ratheesh K J wrote: > > Hello All, > > > > I run a select query to see its speed. It took around 5 seconds. Now i > > run the same query simultaneously twice usng two instances of the client > > tool. It took 10 seconds for both the queris to complete. Its not 5 secs > > + 5 secs. Both the queries were running till 10 secs when i saw using
> In the case of a single disk serving up the data, two simultaneous queries > for the same data will cause the disk to go back and forth trying to > satisfy each query. Even with a mirrored pair of disks, you're going to > have problems unless you have a very intelligent disk controller that can > split the requests across the two disks. Forgot to add - do the queries require table locks? If so, the first one is going to lock the table, run in 5 seconds, unlock. Then the second one, and then the third. Assuming no query cache. -- Scanned by iCritical. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
