Help with high LA

[scuba at centroin.com.br]

Hi All,

I need help for some strange problem with one of my servers, that can cost 
my job.

It's a FreeBSD 7.0-RELEASE-p5/amd64 running on a Dell PowerEdge III as a 
Virtual machine of VMware ESXi. There are only two VM in this box, and one 
of them (basicly a mail server) is running fine.

The problem is with high loads on the other one, that runs (besides other 
services) http and pop3.

TOP show LA from 40 to 90 most of the time.

I thought, at first, that was a disk botleneck due to some big mailboxes, 
or something related to some Apache (2.2.9) fine tuning, but it's 
something else.


If I stop pop3 and apache services (the most active of the box), the LA 
drops to 1~2.
Starting only one of them (any one) the LA rise to 20~40. Sugesting that 
it's not tied to a specific service.

I did a test running just pop3 (Qpopper), pointing the mail spool to a 
empty directory, to make shure that it's not a disk problem. And the LA 
also goes to sky (~30). The same happens with only apache running pointing 
to a simple http page.

The console shows messages like:

ipfw: install_state: Too many dynamic rules

I know I must review my rules and limit the number of keep-state entries, 
but a tryed to rise the number of dynamic buckets via sysctl:

sysctl -w net.inet.ip.fw.dyn_buckets=2048

But it seems it's not working, since the number of current buckets doesn't 
pass 256:

net.inet.ip.fw.curr_dyn_buckets: 256

I tryed to make some OS tuning, from the handbook, like increase the 
maxcon:

kern.ipc.somaxconn: 2048

but nothing seems to work.

Other entries in the logs:
Feb 12 09:06:20 host1 inetd[1248]: accept (for ftp): Software caused 
connection abort
Feb 12 09:06:20 host1 inetd[1248]: accept (for pop3): Software caused 
connection abort

I need some clues to undestand what is happening.

Thank you,

  - Marcelo