OK, sorted the problem by upping both the kernel semaphore settings and
the firebird.conf setting:

respectively :

kernel.sem="1024 64000 1024 512"

and

LockSemCount = 512

This allows 300 concurrent connections to exist, and for the MON$ queries
to succeed.

However, selecting from the MON$ tables is pretty slow, and basically
everything else stops while the query executes.



Regards

Vince




Vince Duggan
I.T. Manager (Business Systems)
Virgin Active South Africa
Tel (+27) (0)21 684 3525
Cell (+27) (0)82 907 2086

This e-mail and its contents are subject to a disclaimer, which can be
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firebird-support@yahoogroups.com wrote on 05/03/2009 05:15:58 PM:

> vince.duggan@...
> Sent by: firebird-support@yahoogroups.com
>
> 05/03/2009 05:15 PM
>
> Please respond to
> firebird-support@yahoogroups.com
>
> To
>
> firebird-support@yahoogroups.com
>
> cc
>
> Subject
>
> {Disarmed} Re: {Disarmed} [firebird-support] Select count(*) from
> mon$attachments kills connections
>
> Just noticed that this is linked to a 'semaphores exhausted' error in

the

> log file.
>
> However, I can run all these attachments without any errors for as long

as

> I wish, with no problems. It is only when the 'Select count(*) from
> mon$attachments' is executed that the problem arises.
>
> I will up my semaphores and see where this gets me...
>
> Regards
>
> Vince
>
> Vince Duggan
> I.T. Manager (Business Systems)
> Virgin Active South Africa
> Tel (+27) (0)21 684 3525
> Cell (+27) (0)82 907 2086
>
> This e-mail and its contents are subject to a disclaimer, which can be
> viewed at http://www.virginactive.co.za/disclaimer/disclaimer.htm .

Should

> you be unable to access the link, please e-mail
> disclaimer@... and a copy of the disclaimer will be
> e-mailed to you.
>
> firebird-support@yahoogroups.com wrote on 05/03/2009 04:48:15 PM:
>
> > vince.duggan@...
> > Sent by: firebird-support@yahoogroups.com
> >
> > 05/03/2009 04:48 PM
> >
> > Please respond to
> > firebird-support@yahoogroups.com
> >
> > To
> >
> > firebird-support@yahoogroups.com
> >
> > cc
> >
> > Subject
> >
> > {Disarmed} [firebird-support] Select count(*) from mon$attachments
> > kills connections
> >
> > Hi all,
> >
> > Running FirebirdCS-2.1.1.17910-0.amd64 under Linux Fedora core 9

version

>
> > 2.6.27.15-78.2.23.fc9.x86_64
> >
> > When the database is under a high load(i.e. over 100 connections)

where

> > each connection is doing queries and updates, then merely executing
> > 'select count(*) from mon$attachments' causes several of the

connections

>
> > to die. Client apps report 'error reading data from the connection'.
> >
> > Is this a known bug?
> >
> > Regards
> >
> > Vince
> >
> > Vince Duggan
> > I.T. Manager (Business Systems)
> > Virgin Active South Africa
> > Tel (+27) (0)21 684 3525
> > Cell (+27) (0)82 907 2086
> >
> > This e-mail and its contents are subject to a disclaimer, which can be

> > viewed at http://www.virginactive.co.za/disclaimer/disclaimer.htm .
> Should
> > you be unable to access the link, please e-mail
> > disclaimer@... and a copy of the disclaimer will be
> > e-mailed to you.
> >
> > --
> > This message has been scanned for viruses and
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> >
> > [Non-text portions of this message have been removed]
>
> >
> --
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>

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