mysql strangely slow

paulsim

Hi Folks

I have two Celeron 850 computers running almost identically. Apache2, PHP4 and Mysql 4.

One is on-line, the other is my development computer.

On long pages that have a few hundred select or insert queries, the on-line machine takes say 13 seconds, the development machine takes 130 seconds; yes 10 times the time.

It is hard to see any difference in the two machines. It is not the computer as I can swap over the drives and the same drive is always the slow one. I have re-installed Apache, PHP and MySQL. I have tried MySQL 5 as well as 4.

A large number of warnings written to a log file can slow up a machine drastically; but this is not happening here.

I have re-installed Windows 2K. No diff. I have tried Windows XP. No diff.

I have tested disk speed with a disk speed testing program; drive writes and reads multi times OK.

I have tried word loading a large HTM filel that it has to decode; speed is the same as other machines.

Where else to look????

Any suggestions greatly appreciated.

Paul

tomhath

Verify that the databases are the same. Take a close look at indexes, also check storage engine types (innoDB vs ISAM).

Then run MySQL's EXPLAIN on some of the queries involved and see if there are differences. But my guess it that the development machine is missing some indexes.

Roger_Ramjet

Look to winders itself, that is the main difference between the 2 systems. Specifically, one is online and functioning fine so it must be fully integrated into a network with DNS and routing properly configured. The other is presumably not well integrated into anything. Something is making the operating system slow; which does not surprise me in the least.

Look at any differences in the running processes, look to your interface configuration for dns and run the network monitor to see what is going on there. If dns is misconfigured then your development machine could just be waiting around for lots of unneccessary, or unresolved dns calls. If you are running AD then there is a blackhole of performance problems right there.

I presume you have looked into the timing of each query, are they all 10 time slower?