Joern Janoschek wrote:
>
> Hi,
>
> we are currently developing several Perl scripts for a big
> german site with high traffic and the need of fast DB
> connections. The webserver are Apache 1.3.14 setup with mod_perl
> (current version as far as I know). The scripts connect to a
> Mysql 3.2332 on another machine over a socket connections.
> Now the problem: High traffic result to many connections to the
> DB. The DB seems to be fast enough (4 Xeon 750 machine with 4
> GB) to handle those requests. BUT after some time the DB get
> flooded by unauthorised connections. Looking at the DB server
> stats it doesn't look like a high demand for processor power...
> the machine is idling as far as a DB server can be idle. Those
> faulty connection, we can't get rid of. Once they are coming in,
> the DB doesn't seem capable of handling, authenticating or
> refusing them properly.
> We regard this as a some sort of mod_perl socket problems
> because performance tests during the night, using PHP with the
> same queries and similar load proof to be all correctly
> answered. No unauthenticated connection in the processlist of
> the mysql, even when there are 500 concurrent DB requests
> running.
> Taking a peek at the webserver netstats when connecting with
> Perl scripts show a lot of open and not closing socket
> connections to the mysql... only after some timeout period they
> get disconnected.
> Currently Perl tests over mod_cgi still have to be made, but I
> doubt this will be a problem, but who knows... maybe we have
> some DBD::mysql configuration problem here? This is surely the
> wrong list to ask... :-) but you'll never know, maybe sonmeone
> reading this can point me in the propper direction.
>
> Anyway, anyone experienced the same behaviour before? Any hint
> to a solution are greatly appreciated, we need a
> fix/solution/workaround soon!
>
> A word on Apache::DBI: Yes, we did try persistant connections to
> avoid heavy connection load on the mysql. BUT it simply didn't
> work. Well sort of. Persistant connections were established, but
> they never got reused. Until about 70000 open connections
> resulted in a DB crash. Not nice. Same problem with a
> corresponding persistant connection test using PHP... maybe a
> Mysql client source configuration problem or something like it?
> Anyone experienced this before?
>
There's no reason why Apache::DBI should not work - by the sounds of it
the connections strings may have been different ?
Apache::DBI works in an environment where on user ID is used to connect
to the DB mulitple time. If you use two different connection strings
Apache::DBI will try and make both persistent (IIRC).
So check your DBI connection strings as they should be indentical.
Greg
> Thanks for any help or hint,
>
> Jörn Janoschek.
> KLAHOLD - We make IT work! - http://www.klahold.de
> - WebDevelopment - http://www.klahold.de
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