On Wed, 9 May 2007, Daniel Ouellet wrote:
> Otto Moerbeek wrote:

quoted text
> > > Where are the OS bottleneck that I can may be improve here?

> >

> > Loks at the memory usage. 300 httpd procces could take up 3000M

> > easily, especially with stuff like php. In that case, the machine

> > starts swapping and your hit the roof. As a general rul, do not allow

> > more httpd procces than our machine can handle without swapping. Also,

> > a long KeepAliveTmeout can works against you, by holding slots.

>

> Thanks Otto,

>

> I am still doing tests and tweak, but as far as swap, I checked that and same

> for keep alive in httpd.conf and I even changed it in:

>

> net.inet.tcp.keepinittime=10

> net.inet.tcp.keepidle=30

> net.inet.tcp.keepintvl=30

These parameters do not have a lot to do with what you are seeing.
I was talking abouty the KeepAliveTimeout of apache. It's by default

15s. WIth a long timout, any processs that has served a request will

wait 15s to see if the client issues more requests on the same

connection before it becomes available to serve other requests. For

more details, see http://httpd.apache.org/docs/1.3/mod/core.html#keepalivetimeout
>

quoted text
> For testing only. I am not saying the value above are any good, but I am

> testing multiple things and reading a lot on sysctl and what each one does.

>

> KeepAliveTmeout is at 5 seconds.

Try lowering it even more.
>

quoted text
> No swapping is happening, even with 1000 httpd running.

>

> load averages: 123.63, 39.74, 63.3285                      01:26:47

> 1064 processes:1063 idle, 1 on processor

> CPU states:  0.8% user,  0.0% nice,  3.1% system,  0.8% interrupt, 95.4% idle

> Memory: Real: 648M/1293M act/tot  Free: 711M  Swap: 0K/4096M used/tot