Re: PGconn thread safety

On Fri, 7 Feb 2003, Lee Kindness wrote:

> Well the areas I have patched would have /potentially/ caused
> inaccurate error messages (using global errno). Also potential
> corruption on connect to database if 2+ threads were trying to do this
> at once - a non-threadsafe fucntion was being used to retrieve all
> local usernames.
>
> I've been a bit busy of late, the code itself is submitted to
> pgsql-patches but configure work is still to be done.
>
> L.


in my connection pool, all connections are made _before_ any thread access
takes place.  the pool will be used mostly for cgi programs so i really don't
care about error messages too much (seems like using res = PGExec might fix
this issue?) so it seems like my application may not need thread protection.

-a


>
> Shridhar Daithankar writes:
>  > On Friday 07 February 2003 12:44 pm, you wrote:
>  > > Neil Conway <neilc@samurai.com> writes:
>  > > That's the theory anyway.  I believe it actually is free of unsafe uses
>  > > of static variables.  However, someone recently pointed out that it uses
>  > > some libc routines that probably aren't thread-safe; so there's some
>  > > cleanup yet to do before we can claim real thread safety.
>  >
>  > Well, I ran a mutlithreaded test where around 30 connections were hammered in
>  > a mutlihtreaded servers using libpq for 100,000 transactions. I didn't notice
>  > any data inconsistency.
>  >
>  > Only noticable thing was that postgresql was not returning even simplest
>  > result in less than 200 ms. So in order to achieve a good throughput, I had
>  > to up the number of connections. The max throughput. was 200ms/no. of
>  > connections.
>  >
>  > but that is a different issue..
>  >
>  >  Shridhar
>
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