>>>>> "Piyush" == Piyush Ranjan <piyush...@gmail.com> writes:
Piyush> 8 mongrels are way too much capacity. Do you need that many ?
Mongrels
Piyush> taking 300MB is not unheard of as James said. Are you using loads of
Piyush> libraries or cache in memory ? Moreover counting per mongrel memory
is not
Piyush> so easy. If they use shared libraries the memory per process shoots
up in
Piyush> the "ps auwx" command but actual memory usage is not that
Piyush> high.
ps auwx output:
xdsott003-[~] mcr 1256 %ps auwx
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.2 1704 540 ? Ss Jun18 0:00 /sbin/init
root 2 0.0 0.0 0 0 ? S Jun18 0:00 [migration/0]
...
The VSZ gives the total virtual size.
The RSS gives the resident set size.
If RSS is staying small-ish, and VSZ is climbing, then you have a memory
leak (inside the process) of some kind. The leaked memory will be pushed
into swap.
If you run "lsof -p XXX" on the PIDs of the mongrels:
mustang-[~] mcr 1093 %lsof -p 15305
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
mongrel_r 15305 xas2 cwd unknown /proc/15305/cwd
(readlink: Permission denied)
mongrel_r 15305 xas2 rtd unknown /proc/15305/root
(readlink: Permission denied)
mongrel_r 15305 xas2 txt unknown /proc/15305/exe
(readlink: Permission denied)
mongrel_r 15305 xas2 mem REG 8,1 3336 266044 /usr/bin/ruby1.8
mongrel_r 15305 xas2 mem REG 0,0 0 [heap] (stat: No such
file or directory)
mongrel_r 15305 xas2 mem REG 8,1 38372 170534
/lib/tls/i686/cmov/libnss_files-2.3.6.so
mongrel_r 15305 xas2 mem REG 8,1 76548 170528
/lib/tls/i686/cmov/libnsl-2.3.6.so
You can see the size of each shared object. Mostly, they will all be
loaded by the time that the mongrel has served a few requests. (It is
certainly possible that you only load some other things later on, if so,
there is an easy out)
I have not seen my mongrels grow to 300M each. Typically, they are 90
to 100M, but I do not do a lot of caching, etc.
I think it is worth writing some perl scripts to try to characterize if
your mongrel grows to 300M quickly, or slowly. You might do this
externally (in perl/shell/awk/), or you could do it inside of mongrel by
using /proc/self to self-examine and lot sizes on each request.
I agree that having 8 mongrels may not be the best idea --- depends upon
how much CPU and RAM you have. I planned to have have 4 per single-CPU
virtual machine, and scale horizontally with additional application
servers.
(Someone has a patch to have capistrano turn off one mongrel at a time
during a deployment, but I do not recall where)
--
Michael Richardson <m...@simtone.net>
Director -- Consumer Desktop Development, Simtone Corporation, Ottawa, Canada
Personal: http://www.sandelman.ca/mcr/
SIMtone Corporation fundamentally transforms computing into simple,
secure, and very low-cost network-provisioned services pervasively
accessible by everyone. Learn more at www.simtone.net and www.SIMtoneVDU.com
_______________________________________________
Mongrel-users mailing list
Mongrel-users@rubyforge.org
http://rubyforge.org/mailman/listinfo/mongrel-users
