> I finally tracked this down to hyperthreading. Since I
> could not disable hyperthreading, I switched to the
> Classic version of Firebird - expensive on resources,
> but it works.

This should also increase the response time from FB when running large
queries, as each fb_inet_server can be scheduled independently by the kernel
and utilize the two (virtual) processors.

> Setting the "affinity" on Linux seems to have no
> effect on which "CPU" Firebird runs - it seems to
> ping-pong from CPU to CPU.

From memory, the firebird.conf says that the CPU Affinity is for Windows
Only.

> Note: I believe not all RedHat Linux versions support
> hyperthreading - to check if your OS/CPU is
> hyperthreaded , run the "top" program . If it shows 2
> CPUs you have a hyperthreaded (or SMP) machine.

On a single processor HT machine, linux will utilise two processors if HT is
turned on in the bios and smp is enabled in the kernel. Recompiling the
kernel with smp support should allow you to use HT.

Cheers,

Ryan Thomas
TransActive Systems

P: (02) 4322 3302
F: (02) 4325 1141
E: ryan@...
W: http://www.transactive.com.au/

> Helen, thank you for the response - it is greatly
> appreciated.
>
> --- Helen Borrie <helebor@...> wrote:
>
> > At 12:28 AM 20/09/2005 +0000, you wrote:
> > >I am having severe problems with Firebird on RedHat
> > Linux. Here are
> > >the steps I followed:
> > >
> > > I first installed
> > "FirebirdSS-1.5.2.4731-0.i686.rpm". Using this, my
> > >application (which runs on multiple boxes and uses
> > the JDBC driver)
> > >runs for about 18-24 hours, after which Firebird
> > hangs. Everything
> > >hangs, including isql, which times out after a long
> > time during the
> > >connect with the error:
> > >
> > >Statement failed, SQLCODE = -902
> > >Unable to complete network request to host
> > "localhost".
> > >-Failed to establish a connection.
> > >
> > > I then tried the NPTL version
> > "FirebirdSS-1.5.2.4731-nptl.i686.rpm",
> > >since I read posts that indicated this would fix
> > the problem.
> > >However, this made the problem even worse - my
> > application hangs in
> > >the first 15 minutes with the same symptoms.
> > >
> > > I am using RedHat with the 2.6 Kernel (I believe
> > this uses NPTL).
> > >The output of cat/proc on my system yields:
> > >
> > >Linux version 2.6.8.1 (root@linux745) (gcc version
> > 3.2.3 20030502
> > >(Red Hat Linux 3.2.3-24)) #16 SMP Fri Sep 10
> > 12:57:04 EDT 2004
> > >
> > > Are there any logs that I can look at which
> > will help locate the
> > >problem? I am wondering if building Firebird from
> > the sources on the
> > >same hardware that it runs on will help - how can I
> > build a new RPM
> > >from scratch? (I am a Linux newbie)..
> >
> > Look in firebird.log to see whether you have any
> > network problems being
> > reported there. It looks as if something is
> > crashing the server and
> > Guardian can't get it to come up again. "Something"
> > might be anything,
> > e.g. hyperthreading active, or the processor
> > affinity (CPUAffinityMask in
> > firebird.conf) having been set to something other
> > than 1; or long-running
> > transactions that simply exhaust system resources;
> > or a rogue UDF that is
> > crashing the server; or more connections than the
> > host machine has
> > resources to handle; or leaking connections from
> > wrong cleanup by your
> > applications; or a cron job that is trying to do a
> > file-level backup on an
> > active database file; or ...(how long is a piece of
> > string?)
> >
> > Make sure that the database file is located on a
> > hard disk that is
> > physically attached to the host machine, i.e. not
> > accessed on a different
> > box through Samba, NFS, NIS, etc.
> >
> > If you don't get a solution from this list, try
> > posting a question to the
> > firebird-java list. Make sure you provide all the
> > ennvironment details,
> > including the exact version of Jaybird you are using
> > for the client --
> > including OS platform -- and how your application
> > code is handling
> > attachments and detachments.
> >
> > ./heLen
> >
> >
> >
> >
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> >
> --------------------------------------------------------------
> ------~->
> >
> >
> >
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> >
> > Visit http://firebird.sourceforge.net and click the
> > Resources item
> > on the main (top) menu. Try Knowledgebase and FAQ
> > links !
> >
> > Also search the knowledgebases at
> > http://www.ibphoenix.com
> >
> >
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> >
> > Yahoo! Groups Links
> >
> >
> > firebird-support-unsubscribe@yahoogroups.com
> >
> >
> >
> >
> >
>
>
>
>
> __________________________________
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>
> ------------------------ Yahoo! Groups Sponsor
> --------------------~-->
> Fair play? Video games influencing politics. Click and talk back!
> http://us.click.yahoo.com/T8sf5C/tzNLAA/TtwFAA/67folB/TM
> --------------------------------------------------------------
> ------~->
>
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>
> Visit http://firebird.sourceforge.net and click the Resources item
> on the main (top) menu. Try Knowledgebase and FAQ links !
>
> Also search the knowledgebases at http://www.ibphoenix.com
>
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>
> Yahoo! Groups Links
>
>
>
>
>
>
>