I've been experimenting some problems about MySQL connections too. Aparently connections with MySQL wasn't closed (or something like that) and the server's load started to grow up. At the begining, I thought that the problem was in MySQL's configuration (timeouts, etc); but it wasn't. I improved the MySQL connections when I recompiled MySQL as static and then recompile vpopmail; it spend more server's memory I know, but the connection close faster. When my POP3 server reach approximately 100 connections/second, the problem come back, but not so hard as before static compiled. Perhaps, the complete solution for high load servers using vpopmail and MySQL will be SQLRelay (for connection pooling).
It's my two cents.
Dave Goodrich wrote:
Tom Collins wrote:
On Oct 19, 2004, at 8:14 PM, Charles Sprickman wrote:
The one thing that kind of grabbed people's interest was the flood of "connection dropped" messages that mysql will log if I enable the "log warnings" option. On other mysql installations I can leave this on and I just see the occasional error. If I point vpopmail at a db with the logging enabled, it just scrolls errors like mad.
Is there any way to find out what program was responsible for creating the connection that was dropped? Can you add additional logging to find out what queries are made on the dropped connections before they get dropped? If there's a pattern, we might be able to track down the offending program and fix it.
I have plenty of logging, the querys are in one log, and the errors are in other. The query log is not timestamped consistantly, IE not every record. Makes determining a cause tough. I can see only what DB was accessed and by what user, pass, IP.
I've been trying to get better logging, the mysql list, and forums have not responded. I'm hitting a dead end as far as getting more information.