Ian,I'm cross posting this to [EMAIL PROTECTED]
I had been a user of Apache 1.3 and mod_gzip, but I recently upgraded to Apache 2.0 and I'm trying to use mod_deflate.
I got it working fairly well, but it's causing high load and page timeouts during peak periods of operation for my site.
The output I'm compressing is generated from mod_perl scripts.
mod_gzip had not had this problem. It's possible that there are other factors (the whole system was upgraded), so I can't absolutely blame mod_deflate, but removing it certainly fixes the load problem.
sounds like a cpu load issue.
I've been dropping the DeflateCompressionLevel, which seems to help, but I'm already down to 2 and I'm still getting timeouts.
I find that surprising.. the reason I do is when I put it on one of our production machines we saw a 10% in cpu load, but no timeouts (we used the hard-coded value of '1' then)
what do you mean by 'timeouts'.
Is there any other way I can improve the efficiency of it?
first.. I would examine the cpu utilization/throughput of your box.
maybe even reverting to 1.3.x/mod_gzip for a period and see if that works for you.
not directly.. most of the time spent is in zlib's library, and the standard filter routines that apache uses.
Would changing DeflateBufferSize from 8096 to something else, help?
Are there any plans to improve the efficiency of mod_deflate in the future?
I'm running Apache/2.0.46 (prefork MPM) and mod_perl-1.99_09 on Red Hat 9. Server has dual 800Mhz CPUs and 1.5GB ram.
may I suggest you move to the worker MPM, I'm thinking you don't have enough ram in your machine for a pre-fork/mod-perl combo.
we run with 32 threads, and it seems ok most of the time.
just be careful of your 3rd party perl modules.. some may not be threadsafe.
([EMAIL PROTECTED] would be the appropiate place to ask about that)
Thanks
-bill
regards ian
