|
We used mod_log_spread for about 6 months at Adicio, Inc. We were
pumping 4-8 million hits per day, reaching rates of 600-1000 hits per
second at times, across 8 servers through it. I even submitted a few
patches and we paid the author, George Schlossnagle, to enhance it to be
more robust for us.
We gave up on it ultimately, as the underlying toolkit, spread, wasn't
scaling for us. We'd have a little network blip on one machine, and the
whole ring would stop working for 5 minutes. Server loads would go up
retrying, and retransmitting, error logs would be flying. It was a real
mess.
Ultimately we needed to do some tuning that involved recompiling the
spread daemon. I gained a deep understanding of the spread protocol, and
decided it was far too complex for this purpose.
We've gone to a system now where logs are written locally using the
program 'cronolog' and once per hour they are collected via NFS export.
It works pretty well, though it was nice to have one big log file.
On Thu, 2006-05-04 at 11:55 +0200, Lasse Karstensen wrote:
> Graeme Fowler:
> > You could do that. Or you could use mod_log_spread:
> > http://www.backhand.org/mod_log_spread/
> > This makes use of the multicast spread toolkit to allow you to log
> > messages to remote servers. The mechanics of it I leave to you as they
> > aren't hugely simple.
>
> I tried compiling mod_log_spread a few months ago, even found a
> apache2 patch on some mailling list, but without luck.
>
> Anyone succeeded using it with apache2?
>
> The project seems abandoned. Too bad, we used it before and
> were mostly happy.
>
>
> > Alternatively, make Apache log to a remote syslog host which combines
> > the logs for you. This could easily be *both* of your realservers
> > logging to each other, and again I leave the mechanics of it to you.
> > Note that this will not scale up or out very far, but for a two-node
> > solution it's perfect IMO.
>
> Which is the solution we are using now. What kind of scaling issues
> are you predicting? We're having 10-12 realservers now, with some
> moderate amounts of traffic.
>
>
|
