[OT] Replacing reverse squid with mod_proxy
We are currently using squid set up as a reverse proxy to accelerate several heavy backends (mod_perl, etc) and to protect them from slow client connections. I am looking into replacing the squid with apache+mod_proxy. Why? Because ultimately I'd like to be able to cluster the frontend using mod_backhand + wackamole. The primary reason for clustering isn't for load-balancing (yet) but for failover handling. So, ideally, one machine should be enough to serve the whole server load. Speaking of load, the squid (2.3.STABLE1) is currently doing up to 80 requests per second at a cache hit ratio of around 72%. This is on one box, a Dual 500MHz Pentium III with 1GB RAM. Average object size is 6KB. 200/304 ratio is around 5/3. Now, I've tried to replace the squid with apache+mod_proxy (1.3.11) and the frontend very quickly came to a standstill. I set MaxClients to 256 but all slots filled up fast. I upped MaxClients to 512 (recompiled with patched httpd.h) but the result was the same. All slots were occupied in no time and the server ground to a halt. Now I'm left with two choices: give up or try harder :-) Before I decide for one of them I thought I'd ask on the lists (sorry for the x-post) to see if the above numbers (80 Hits/Second) are in fact feasible with apache/mod_proxy on one box. Are there any benchmarks around? Does someone have a similar setup and how many requests can they serve? Should I up MaxClients any further? Will I get better results using a newer version of apache? Or should I give up and stick with squid? TIA for your input.
Re: Be carefull with apache 1.3.24
John Siracusa [EMAIL PROTECTED] on Mar 25, 2002: Does anyone know how I can put my ProxyIOBufferSize config line in a conditional that'll keep it from blowing up if I'm using a version of apache earlier than 1.3.24? You could use IfDefine but that would mean that the command that starts apache needs to be aware of which version you are using and modifying startup params accordingly. See http://httpd.apache.org/docs/mod/core.html#ifdefine
Re: problems with $r-status('OK')
clayton cottingham [EMAIL PROTECTED] on Mar 4, 2002:
every time i use
the $r-status('OK');
OK in this context is not a string, but a constant that is defined in
Apache::Constants. Modify your code like this:
use Apache::Constants qw(:common);
...
$r-status(OK); # No quotes, it's a constant
HTH, Hans
Re: [OT-ish] Session refresh philosophy
David Harris [EMAIL PROTECTED] on Feb 19, 2002: The encoded information is [...] split into reasonable length hidden fields. Why not put everything in one field? Are there restrictions? Does it make a difference when using POST? Hans
Re: PerlPassEnv and Proxies
Andrew Green [EMAIL PROTECTED] on Feb 18, 2002: As part of this, I'm trying to allow a prefix to the URL path to set an environment variable I can then use in my mod_perl programs to determine databases, templates etc. The vanilla httpd.conf features a line thus: RewriteRule ^/(test|access|ewok)/(.*)$ http://spare.article7.co.uk:8080/page/$2 [P,E=A7_FRAMEWORK:$1,L] (ignoring the wrapping). I also set PerlPassEnv A7_FRAMEWORK in my mod_perl httpd.conf -- but that environment variable always remains undef. The order of the P,E,L flags doesn't seem to make a difference. As others pointed out, you cannot set envivonment variables in the vanilla and expect them to appear out of nothing in the mod_perl server. I have had a similar Problem and got by it like this. You can have two RewriteRules, one in the vanilla and a corresponding in the mod_perl: vanilla: RewriteRule ^/(test|access|ewok)/(.*)$ http://spare.article7.co.uk:8080/ENV_A7_FRAMEWORK/$1/page/$2 [P,E=A7_FRAMEWORK:$1,L] or, if you don't need A7_FRAMEWORK in the vanilla you can omit it here: RewriteRule ^/(test|access|ewok)/(.*)$ http://spare.article7.co.uk:8080/ENV_A7_FRAMEWORK/$1/page/$2 [P,L] mod_perl: RewriteRule ^/ENV_([^/]+)/([^/]+)/(.*)$ $3 [E=$1:$2,PT,L] I agree, its a big hack, but it works :-) HTH, Hans
Re: mod_perl compile problem
OCNS Consulting [EMAIL PROTECTED] on Feb 14, 2002: [mod_perl-1.26]# perl Makefile.PL APACHE_SRC=/dist/apache_1.3.23/src DO_HTTPD=1 USE_ACAPI=1 PREP_HTTPD=1 EVERYTHING=1 ^ Make that USE_APACI=1 Now, I may be missing something and somebody already asked you earlier about this: You are using ActiveState Perl on Linux? I always thought ActiveState Perl is for Windows boxen. No? Hans
Persistent HTTP Connections ala Apache::DBI
I'm working on a web application which obtains data via a legacy system rather than DBI. Using DBI is (unfortunately) not an option. The machine where the web application runs cannot run the legacy system. Thus, the setup looks somewhat like this: DB = DB Query (Legacy) = Apache/mod_perl = Client I was thinking to make the connection between DB Query and Apache/mod_perl using HTTP, so there will be an Apache running on the DB Query tier for access to the legacy system. What I'm interested in, is a persistent HTTP connection between the Apache/mod_perl tier and the DB Query tier. I'm thinking of a ChildInit handler which opens up a HTTP/1.1 connection to the apache sitting on the DB query tier. The connection would use keep-alive, which of course would be enabled and set to high timeout values on the DB Legacy tier. This is more or less what Apache::DBI does, just in this case it should be something like Apache::PersistentHTTPConnection. Unfortunately, I haven't found such a thing. Has anyone done such a thing before? Can someone point me to docs or modules which could help doing this? Or is this whole idea maybe just plain stupid? Are there obvious caveats I haven't thought of? Any comments are welcome.
Apache::DBI Segmentation fault
I am getting a segmentation fault on configtest when using Apache::DBI (using the startup.pl example in Apache::DBI Distribution). When trying to start the server I get no error messages but the server isn't running afterwards: root@ganja:/home/www/server/conf ../bin/apachectl start ../bin/apachectl start: httpd started root@ganja:/home/www/server/conf ps -ef | grep httpd lengerke 5787 27877 0 12:11 pts/500:00:00 vi httpd.conf root 6434 5760 0 12:57 pts/11 00:00:00 grep httpd root@ganja:/home/www/server/conf ../bin/apachectl configtest Syntax OK ../bin/apachectl: line 184: 6436 Segmentation fault $HTTPD -t root@ganja:/home/www/server/conf When I comment out the 'use Apache::DBI' in startup.pl all works fine. Setting $Apache::DBI::DEBUG = 2 makes no difference even in verbosity of the error_log - the server will die without any warning or error. The setup is: SuSE Linux 6.3 (i386) Apache/1.3.20 (Unix) # (enabled proxy, rewrite, so, ssl) PHP/4.0.6 # apxs-built DSO mod_perl/1.26 # apxs-built DSO mod_jk # apxs-built DSO mod_ssl/2.8.4 OpenSSL/0.9.4 Perl 5.005_03 Apache::DBI 0.88 DBI 1.14 # works fine without Apache::DBI Any help or pointers are appreciated. Hans
Re: Apache::DBI Segmentation fault
Uh, sorry forgot to post Database and perl -V... Database is Informix. Summary of my perl5 (5.0 patchlevel 5 subversion 3) configuration: Platform: osname=linux, osvers=2.2.13, archname=i586-linux uname='linux benjy 2.2.13 #4 mon aug 16 11:18:11 mest 1999 i686 unknown ' hint=recommended, useposix=true, d_sigaction=define usethreads=undef useperlio=undef d_sfio=undef Compiler: cc='cc', optimize='-O2 -pipe', gccversion=egcs-2.91.66 19990314/Linux (egcs-1.1.2 release) cppflags='-Dbool=char -DHAS_BOOL -I/usr/local/include' ccflags ='-Dbool=char -DHAS_BOOL -I/usr/local/include' stdchar='char', d_stdstdio=undef, usevfork=false intsize=4, longsize=4, ptrsize=4, doublesize=8 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12 alignbytes=4, usemymalloc=n, prototype=define Linker and Libraries: ld='cc', ldflags =' -L/usr/local/lib' libpth=/usr/local/lib /lib /usr/lib libs=-lnsl -lndbm -lgdbm -ldb -ldl -lm -lc -lposix -lcrypt libc=, so=so, useshrplib=false, libperl=libperl.a Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-rdynamic' cccdlflags='-fpic', lddlflags='-shared -L/usr/local/lib' Characteristics of this binary (from libperl): Built under linux Compiled at Nov 6 1999 15:47:59 @INC: /usr/lib/perl5/5.00503/i586-linux /usr/lib/perl5/5.00503 /usr/lib/perl5/site_perl/5.005/i586-linux /usr/lib/perl5/site_perl/5.005 . Hans Juergen von Lengerke: I am getting a segmentation fault on configtest when using Apache::DBI (using the startup.pl example in Apache::DBI Distribution). When trying to start the server I get no error messages but the server isn't running afterwards: root@ganja:/home/www/server/conf ../bin/apachectl start ../bin/apachectl start: httpd started root@ganja:/home/www/server/conf ps -ef | grep httpd lengerke 5787 27877 0 12:11 pts/500:00:00 vi httpd.conf root 6434 5760 0 12:57 pts/11 00:00:00 grep httpd root@ganja:/home/www/server/conf ../bin/apachectl configtest Syntax OK ../bin/apachectl: line 184: 6436 Segmentation fault $HTTPD -t root@ganja:/home/www/server/conf When I comment out the 'use Apache::DBI' in startup.pl all works fine. Setting $Apache::DBI::DEBUG = 2 makes no difference even in verbosity of the error_log - the server will die without any warning or error. The setup is: SuSE Linux 6.3 (i386) Apache/1.3.20 (Unix) # (enabled proxy, rewrite, so, ssl) PHP/4.0.6 # apxs-built DSO mod_perl/1.26 # apxs-built DSO mod_jk # apxs-built DSO mod_ssl/2.8.4 OpenSSL/0.9.4 Perl 5.005_03 Apache::DBI 0.88 DBI 1.14 # works fine without Apache::DBI Any help or pointers are appreciated. Hans
Re: Apache::DBI Segmentation fault
Hi,
I actually got this to work now. The segfault happens when I load
Apache::Registry before Apache::DBI. However, I have used the
eg/startup.pl from the Apache::DBI distribution and that has
Apache::Registry loaded before Apache::DBI... Maybe this is a bug?
My httpd.conf Perl* relevant parts:
LoadModule perl_module libexec/libperl.so
[...]
PerlRequire /home/www/server/conf/startup.pl
PerlFreshRestart on
[...]
PerlModule Apache::Registry
DirectoryMatch /home/www/hosts/[^/]*/cgi-perl
Options FollowSymLinks ExecCGI
SetHandler perl-script
PerlHandler Apache::Registry
PerlSendHeader On
AllowOverride None
Order allow,deny
Allow from all
/DirectoryMatch
[...]
Location /perl-status
SetHandler perl-script
PerlSetVar StatusOptionsAll On
PerlHandler Apache::Status
/Location
and the (fixed) startup.pl:
#!/usr/local/bin/perl -w
$ENV{GATEWAY_INTERFACE} =~ /^CGI-Perl/ or die GATEWAY_INTERFACE not Perl!;
use Apache::DBI;
use Apache::Registry;
use strict;
$Apache::DBI::DEBUG = 2;
Now if Apache::Registry is loaded before Apache::DBI in startup.pl I get
the segfault. Also, If I don't use startup.pl and put a 'PerlModule
Apache::DBI' _after_ the 'PerlModule Apache::Registry' in my httpd.conf
I also get the segfault. I am aware that any modules that use DBI must
be loaded _after_ Apache::DBI but I didn't think Apache::Registry uses
DBI, or does it?
Hans
Perrin Harkins:
I am getting a segmentation fault on configtest when using Apache::DBI
(using the startup.pl example in Apache::DBI Distribution). When trying
to start the server I get no error messages but the server isn't
running afterwards
Do you know that your DBI works without Apache::DBI? It would be helpful if
you could post the relevant parts of your httpd.conf and startup.pl too.
- Perrin
