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From:Mike Robinson Date:May 13 2002 7:40pm
Subject:RE: MySQL load problems - gcc-2.96?
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Vadim P. writes:

> Mike, what kind of problem? What exactly goes wrong with PHP4?
>
> Thanks,
> Vadim
>
> Mike Robinson wrote:
> >
>
> > I am able to reproduce this problem very easily, including on
> > Redhat-7.2. Basically, any app using the libmysqlclient.so
> > compiled with gcc-2.96 connecting to a server compiled with
> > gcc-2.96 will experience problems. This is particularly the case
> > with PHP4.
> >

In my case[s], compiling mysql with gcc-2.96 provides a libmysqlclient.so
which in turn is used when compiling PHP4 with external mysql libs (as
opposed to the internal libs bundled with PHP.

Whether or not connecting to mysql with PHP, but particularly so, if there
are more than [anywhere from] 10-25 concurrent connections, the php script
making the connection will experience unexpected results. On some machines,
I've seen 'connection timed out' errors written in the mysql error log. On
other
machines, I've seen nothing written to any log, the error is undetectable
other
than the php script not getting a connection. Just to throw a loop into the
whole thing, about 1 in every 6 tests accepted a decent load, say 50-60
concurrent connections without a problem.

I've just reproduced this problem on 7 machines, in 7 tries. So I'm batting
a thousand on reproducing the problem.

At first blush, I'd say the client wasn't releasing the connection handle,
or
it was doing something to it other than releasing it, and apps needing
connections to mysql were hitting some artificial wall.

Again, switching to the mysql.com binaries didn't provide the fix. I had
to recompile PHP with the static mysql client libs supplied in the binary
download. Then the problem went merrily away.

I've not done the test with the client libs provided by PHP. I can't really
try
that configuration on my machines; I use other apps that use mysql so I
have to use external libs. I have to wonder how many machines out there
are affected by this. If one uses the mysql rpms supplied with their
RedHat-7.x
distribution, they're succeptible to this issue. Its a huge WTF.

Best Regards
Mike Robinson










Thread
MySQL load problems - gcc-2.96?Mike Robinson12 May
  • Re: MySQL load problems - gcc-2.96?Jeremy Zawodny12 May
  • Re: MySQL load problems - gcc-2.96?Alexander Keremidarski13 May
    • RE: MySQL load problems - gcc-2.96?Mike Robinson13 May
      • Re: MySQL load problems - gcc-2.96?Vadim P.13 May
        • RE: MySQL load problems - gcc-2.96?Mike Robinson13 May
      • Re: MySQL load problems - gcc-2.96?(Trond Eivind Glomsrød)14 May
        • Re: MySQL load problems - gcc-2.96?(Trond Eivind Glomsrød)15 May
  • Re: MySQL load problems - gcc-2.96?Vadim P.13 May