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From:Michael Widenius Date:January 27 2001 4:51pm
Subject:Re: MySQL parallel server [long mail]
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Hi!

>>>>> "Mauricio" == Mauricio Breternitz <mbjsql@stripped> writes:

Mauricio> Denis:
Mauricio>       Salut!

Mauricio>       Looks like we have been chasing similar issues. (I am trying to
Mauricio> get several MySQL servers in a  a system that has some similarities with 
Mauricio> yours, albeit in a different environment. The system has several processors 
Mauricio> that can see a shared disk, but also shared memory (in addition to local 
Mauricio> memory).

Mauricio>       The symptoms that you describe appear to stem from caching.
Mauricio> I am studying the source at this moment, and would like to point you to
Mauricio> functions like flush_io_cache and flush_key_blocks. Perhaps you
Mauricio> could change the code to invoke those functions at the end of each
Mauricio> query before you release the file locks to make sure all changes are 
Mauricio> reflected globally.

This is done by default.

Mauricio>        By the way, did you only change the fcntl calls in sql/locks.cc ?
Mauricio> I am under the impression that one would have to change the locks in
Mauricio> thr_lock.cc also.

If run with --enable-locking (or not --skip-locking) then MySQL will
first do an external lock (flock) and then an internal lock (thr_lock)
for each table.

In Denis setup, he don't need to worry about thr_lock at all.

Mauricio>                best regards
Mauricio>                               Mauricio

Regards,
Monty
Thread
MySQL parallel server [long mail]Denis Pithon26 Jan
  • Re: MySQL parallel server [long mail]Sasha Pachev27 Jan
  • MySQL parallel server [long mail]Michael Widenius27 Jan
  • Re: MySQL parallel server [long mail]Paul Cadach28 Jan
Re: MySQL parallel server [long mail]Mauricio Breternitz26 Jan
  • Re: MySQL parallel server [long mail]Michael Widenius27 Jan