High load average mail server 5.3-RELEASE

[mariano benedettini]

I have a mail server running FreeBSD 5.3-RELEASE. It's a dual Xeon with 4gb
of ram.
The server is running Apache (serving Horde) , Postfix, Courier imapd w/SSL,
Amavisd. Also a Postgresql as Horde's storage.
The mail storage is accessed via NFS.
The problem is that it's experiencing a really high load average (see the
top -S ) while the CPU's are relatively idle. I think it's a IO problem
(nfs?), but I cant figure out what exactly is causing this.


top -S:

last pid: 39883;  load averages: 32.40, 15.81, 13.515              up
20+22:51:19  14:13:43
1084 processes:5 running, 1006 sleeping, 73 waiting
CPU states:  6.0% user,  0.0% nice,  2.6% system,  0.1% interrupt, 91.3%
idle
Mem: 1599M Active, 1704M Inact, 311M Wired, 189M Cache, 112M Buf, 14M Free
Swap: 2023M Total, 184K Used, 2023M Free

  PID USERNAME      PRI NICE   SIZE    RES STATE  C   TIME   WCPU    CPU
COMMAND
   11 root          132    0     0K    12K CPU3   3 468.7H 81.30% 81.30%
idle: cpu3
   12 root          132    0     0K    12K CPU2   2 464.0H 80.42% 80.42%
idle: cpu2
   14 root          132    0     0K    12K RUN    0 464.0H 80.27% 80.27%
idle: cpu0
   13 root          132    0     0K    12K CPU1   1 442.6H 70.85% 70.85%
idle: cpu1
32019 www             4    0 33460K 22228K sbwait 1   0:04  1.61%  1.61%
httpd
29620 www             4    0 33900K 22648K kqread 2   0:06  1.56%  1.56%
httpd
39219 root            5    0  5288K  4064K ttyin  2   0:05  1.57%  1.56% top
   78 root          -44 -163     0K    12K WAIT   0 337:32  1.46%  1.46%
swi1: net
17746 icn             4    0  3128K  2032K select 2   0:25  1.32%  1.32%
imapd
   24 root          -64 -183     0K    12K WAIT   0 136:15  0.83%  0.83%
irq11: ohci0
29170 www            20    0 31384K 20144K lockf  3   0:04  0.68%  0.68%
httpd
30476 www            20    0 31392K 20148K lockf  3   0:05  0.63%  0.63%
httpd
31091 www             4    0 32868K 21624K sbwait 3   0:04  0.59%  0.59%
httpd
39712 bnz             4    0  2628K  1668K select 1   0:01  0.69%  0.59%
imapd
32951 www            20    0 27996K 16716K lockf  2   0:03  0.54%  0.54%
httpd
39434 vscan          20    0 19820K 17896K lockf  2   0:00  0.55%  0.54%
perl
   39 root          -68 -187     0K    12K WAIT   2 140:23  0.34%  0.34%
irq26: bge2
36443 vscan          20    0 20492K 18540K lockf  2   0:02  0.34%  0.34%
perl
   79 root          -28 -147     0K    12K WAIT   2 157:14  0.29%  0.29%
swi5: clock sio
  103 root           20    0     0K    12K syncer 3  90:12  0.29%  0.29%
syncer
    4 root           -8    0     0K    12K -      2  64:52  0.29%  0.29%
g_down
37590 vscan          20    0 20620K 18664K lockf  0   0:01  0.29%  0.29%
perl
32942 www            20    0 31612K 20360K lockf  3   0:04  0.24%  0.24%
httpd
33769 pgsql           4    0 20136K 13356K sbwait 2   0:00  0.24%  0.24%
postgres


-- Trafshow bge2:

>From Address                  To Address                    Prot      Bytes
CPS
=====================================================================================
192.168.1.6..978              192.168.1.5..nfsd             udp     5956916
91306
192.168.1.5..nfsd             192.168.1.6..978              udp     1511540
118858
192.168.1.5                   192.168.1.6                   udp     2272172
6259
192.168.1.6                   192.168.1.5                   udp      190084
16715



After searching the lists and documentation, I'm not sure what's
causing the problem.
Suggestions ?

Mariano.

-- 
GMX DSL = Maximale Leistung zum minimalen Preis!
2000 MB nur 2,99, Flatrate ab 4,99 Euro/Monat: http://www.gmx.net/de/go/dsl