Hello all.
I too found out that I sometimes have some action that can take up to 10
seconds in my rails application. I’ve read all arguments Zed made about
polling/and inbox strategies, and I think I just can’t work around my
feeling
that a “wrong” request that takes up too much time should be able to
lock
subsequent requests in mongrels queue. That’s what I have a balancer
for,
right? 
So I tried Robert M.s hint[1] and used
BalancerMember http://foo max=1 acquire=100
to see if that helps. But I may have hit a bug[2], and this does not
work for
me.
Does this work for someone? With what version of Apache? I am running
2.2.4.
Or do all of you have only very fast requests that do not take more than
a
few seconds max to complete? Or do you run a different load balancer?
HAProxy?
I also think that the overall speed of the application would incerase
even
with relatively fast requests, because the balancer would forward the
requests always to a free mongrel that has nothing to do, and can handle
the
request immediately.
BTW, it looks like the acquire parameter is not in seconds, but in
milliseconds, so I tried acquire=100 as well, but no difference.
From[2]
/* Acquire timeout in milliseconds.
* If set this will be the maximum time to
* wait for a free connection.
*/
Maybe this belongs to the Apache ml and not to mongrel, but I think
maybe some
of you hit this problem and solved it somehow.
Another issue: on my system,
mongrel_rails --version
Mongrel Web Server 1.1.3 (installed as a gem)
the --num-procs parameter does not seem to work. To debug the problem I
added
STDERR.puts “TEST: #{worker_list.length} #{@num_processors}”
on line 279 of /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.3/lib/mongrel.rb,
and
to my surprise it looks like the parameter is ignored. If I run it
$ mongrel_rails start -a 127.0.0.1 -p 8999 --num-procs 1 &
[1] 18617
** Starting Mongrel listening at 127.0.0.1:8999
** Starting Rails with development environment…
config/boot.rb:28:Warning: require_gem is obsolete. Use gem instead.
** Rails loaded.
** Loading any Rails specific GemPlugins
** Signals ready. TERM => stop. USR2 => restart. INT => stop (no
restart).
** Rails signals registered. HUP => reload (without restart). It might
not
work well.
** Mongrel 1.1.3 available at 127.0.0.1:8999
** Use CTRL-C to stop.
and then:
$ w3m -dump http://localhost:8999/test >/dev/null
TEST: 0 950
$
So it looks like @num_processors is still at the default value of 950,
and not
1 as I told it on the command line. Does the deprecation warning maybe
have
something to do with this (I don’t think so, but you never know…)?
Thank you!
Simon
[1]http://rubyforge.org/pipermail/mongrel-users/2007-October/004145.html
[2][Apache-SVN] Contents of /httpd/httpd/trunk/modules/proxy/mod_proxy.c
