Subject Re: [firebird-support] Digest Number 7010
Author Steve Friedl
On Mon, Jul 05, 2010 at 11:52:21AM -0000, wrote:
> ________________________________________________________________________
> 2a. Re: Baffling gbak hangups
> Posted by: "Leyne, Sean" Sean@... seanchk_98
> Date: Sun Jul 4, 2010 11:08 am ((PDT))
> Steve,
> > I support some line-of-business software that uses Firebird, and out of
> > dozens of Linux database servers running 2.0.4 Classic (64bit), *one* of them
> > has sporadic hangups during backup.
> Please describe what you mean by "hangs"?

Both the gbak and associated fb_inet_server just sit there just sits
there without chewing any CPU time at all.

> Any error messages, on console? In firebird.log?

No messages of any kind that could conceivably be related. I am in
the firebird and /var/log/messages files all the time, nothing even
with a nearby timestamp.

> Does it "hang" without end, or for a while? If "without end", what is the longest you have waited? If "a while" how long?

Hmmm, I've seen them just sit there for days - let's say 3 or 4? Normally the
backup completes in a few minutes.

As a side note, when it's hung up, fb_lock_print shows *no* Firebird locks
of any kind (backups run while the application is typically idle).

> Is it "hanging" on databases which have been active during the day?

All the databases are active in one form or another during the day, it's
a function of the way the app works to touch each file. I've not found any
pattern as to files hanging being related to anything I can find.

> You might want to add a gstat command ahead of the gbak call, to output the header page stats.
> This would let you know what the state of the database is like before you start (you could see
> if there are any open/long running transactions)

An outstanding idea!

I'll retrofit my backup script to include this step before starting the
backup itself. Perhaps this will tease out a clue...

Thank you!


Stephen J Friedl | Security Consultant | UNIX Wizard | 714 694-0494
steve@... | Orange County, CA | Microsoft MVP |