[rt-users] Performance Issues

[Christian Hammers]

Hello

On Thu, Sep 09, 2004 at 04:41:29PM -0400, Dan Pritts wrote:
> slow meaning a couple seconds to update a page, painful in the 5-10 
> second range.
My problem, too. I read the thread and just wanted to confirm that all
suggestions made no improvement on my system, too.

I'd like to note that the display process is not only slow when printing
the ticket data itself but also when just displaying the top of the
frames or other even the new ticket window...

The record:
  Problem: 4-5s for /rt/Ticket/Display.html?id=1
           with only 1 tiny Ticket in the Database
  Versions: 3.0.11 and 3.2.1
  Handler: Same results with mod_perl, fcgi (2 processes) and speedy
           (with mod_perl and Galeon I see a big load in the browser, too)
  Hardware: celeron600,768MB RAM  and  Athlon2600,1GB RAM
  Disk Activity: no buffer or swap activity reported by vmstat 1
  CPU Activity: 99% during several seconds in top/vmstat, in mason_handler,
                speedy_backend or apache - depending on handler
  Base Systems: Debian 3.1 "sarge" and 3.x "sid" (I'm a @debian.org)
  MySQL Setup: v4.0.20 for large system, using InnoDB and *Query-Cache*
  Browsers tested: Galeon&Mozilla @ Linux, Internet Explorer @ WinXP

Also here some "ps faxu" lines telling which process uses most CPU
power, all those processes were started in the last 10 minutes!

  Sep09   0:36 /usr/sbin/apache
  11:00   0:00  \_ /usr/sbin/fcgi-p
  11:00   0:40  |   \_ /usr/bin/perl /usr/share/request-tracker3.2/libexec/mason_handler.fcgi
> 11:00   1:03  |   \_ /usr/bin/perl /usr/share/request-tracker3.2/libexec/mason_handler.fcgi
  11:00   0:12  \_ /usr/sbin/apache
  11:00   0:01  \_ /usr/sbin/apache
  11:01   0:01  \_ /usr/sbin/apache
  11:01   0:24  \_ /usr/sbin/apache
  11:01   0:12  \_ /usr/sbin/apache
  11:18   0:12  \_ /usr/sbin/apache
  10:59   0:00 /bin/sh /usr/bin/mysqld_safe
  10:59   0:00  \_ /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --pid-file=/var/run/mysqld/mysqld.
  10:59   0:00  \_ logger -p daemon.err -t mysqld_safe -i -t mysqld
  11:01   0:00 /usr/bin/speedy_backend /usr/share/request-tracker3.2/libexec/mason_handler.scgi
> 11:01   0:53  \_ /usr/bin/speedy_backend /usr/share/request-tracker3.2/libexec/mason_handler.scgi
  11:01   0:05  \_ /usr/bin/speedy_backend /usr/share/request-tracker3.2/libexec/mason_handler.scgi
  11:17   0:04  \_ /usr/bin/speedy_backend /usr/share/request-tracker3.2/libexec/mason_handler.scgi
  11:17   0:04  \_ /usr/bin/speedy_backend /usr/share/request-tracker3.2/libexec/mason_handler.scgi
  11:18   0:05  \_ /usr/bin/speedy_backend /usr/share/request-tracker3.2/libexec/mason_handler.scgi
  11:25   0:04  \_ /usr/bin/speedy_backend /usr/share/request-tracker3.2/libexec/mason_handler.scgi

Some nice infos from the MySQL Database showing a working Query Cache:
| Key_blocks_used                | 24       |
| Key_read_requests              | 235      |
| Key_reads                      | 8        |
| Key_write_requests             | 149      |
| Key_writes                     | 53       |

| Qcache_queries_in_cache        | 88       |
| Qcache_inserts                 | 212      |
| Qcache_hits                    | 1646     |
| Qcache_lowmem_prunes           | 0        |
| Qcache_not_cached              | 138      |
| Qcache_free_memory             | 26081032 |
| Qcache_free_blocks             | 9        |
| Qcache_total_blocks            | 206      |

My strace-attached-to-process also show a lot of stats for Perl modules
which I find rather strange as I thought that most of the handlers cache
the modules so that apache must even be reloaded when updating them?
(strace output was sent by someone else, no big differences)

bye,

-christian-


-- 
Christian Hammers             WESTEND GmbH  |  Internet-Business-Provider
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