httpd-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Axel-St├ęphane SMORGRAV <Axel-Stephane.SMORG...@europe.adp.com>
Subject RE: [users@httpd] Problems with Apache 2.2.0 as a conventional proxy
Date Wed, 26 Apr 2006 18:48:58 GMT
There has previously been some discussion on  this list about the virtues of memory caching
versus disk caching. As I recall nobody ever claimed to have observed performance gains using
mod_mem_cache. I have myself not bothered to run any load tests in an attempt to measure the
benefits of mod_mem_cache. The fact is that you virtual file system has the files in memory
anyway, and that using mod_mem_cache you would not benefit from the use of sendfile() as you
would for responses cached on the file system.

Wrt to the core dumps I experienced when using mod_mem_cache and mod_disk_cache, the error
segmentation violation actually occurred in mod_rewrite, but would only be caused if mod_mem_cache
was in use. For some reason it's filed on mod_proxy... http://issues.apache.org/bugzilla/show_bug.cgi?id=35160

-ascs

-----Original Message-----
From: Dan Price [mailto:dp@eng.sun.com] 
Sent: Wednesday, April 26, 2006 8:07 PM
To: users@httpd.apache.org
Subject: Re: [users@httpd] Problems with Apache 2.2.0 as a conventional proxy

On Wed 26 Apr 2006 at 12:41PM, Axel-St?phane  SMORGRAV wrote:
> I had a similar problem when using both mod_mem_cache and mod_disk cache with Apache
2.0.54. I ended up abandoning mod_mem_cache and never experienced the problem again. I may
even have posted a bug report... but back then mod_cache did not get much TLD from developers
who were, as I understand it, busy developing mod_cache for Apache 2.1/2.2.

Thanks for the advice.  Isn't mod_mem_cache a good idea?  Wouldn't it hurt my performance
not to have in-memory caching?

But it turns out that I did explored the different module combinations during my initial testing.
 Turning off mod_mem_cache certainly helped-- but I was still seeing core dumps even without
it, and the text/plain vs.  text/css problem was a real showstopper-- Apache's architecture
makes it nicely guarded against core dumps in child processes, but serving the content incorrectly
is just not OK for my users.

Rather than go back to Squid, for now I have switched to using Sun's proxy server, which is
free but not Open Source, and which has worked better so far.  (I realize that I work for
Sun so this sounds like a commercial but part of what I like to do is use and test free and
open source software; for those interested, see
http://blogs.sun.com/roller/page/dp?entry=installing_sun_java_system_web)
.  I'll reevaluate using Apache for proxying content in the 2.4.0 timeframe, and if I can
find some time, I'll keep trying to debug the (several hundred) apache core files I have.

        -dp

--
Daniel Price - Solaris Kernel Engineering - dp@eng.sun.com - blogs.sun.com/dp

---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
   "   from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org


---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
   "   from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org


Mime
View raw message