Re: [firebird-support] gds_thread_enter contention

> > On Tuesday 06 May 2008, Dmitry Yemanov wrote:
> >
> > <originally posted on the support forums>
> >
> >> Bud Millwood wrote:
> >> > - Does the fbclient library acquire a process-wide lock when a thread
> >> > passes through it (even when connecting to fb-classic)? If so, doesn't
> >> > that counteract the gains we get by running multiple fb-classic
> >> > instances?
> >>
> >> Yes, fbclient is synchronized using some kind of global mutex. It is
> >> acquired when any thread enters the API call and released as soon as the
> >> network packet is ready to be sent to the remote server. So, the
> >> blocking time is very short (compared to the network transport overhead
> >> and the server side processing of the call) and I don't think it really
> >> limits your performance.
> >
> > Hi Dmitry:
> >
> > I grabbed a developer here this morning and went back over our logic and
> > our numbers, and we are both now reasonably sure that this lock *is* the
> > source of the high contention. And from what we can tell, this lock is
> > causing Firebird to fail to scale to its full potential.
>
>     I don't think so.
>
>     Anyway - you may try to use fbclient from current HEAD (v2.5).
> It have no global mutex. Just download snapshot build and test it.