Issues with FlowCleaner on a spam server.

[perikillo]

Hi my friends I have a big issue that I still cannot track what is
causing that my server stop working.

I have a spam gateway running:

spamassassin
clamavis
amavis
apache+mailgraph
postfix
bacula client
apcupsd client

My server is running freebsd 8.0-p2 AMD64. Raid-1.

Copyright (c) 1992-2009 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 8.0-RELEASE-p2 #5: Mon May 10 23:23:20 PDT 2010
    root at filter.oakwest.com:/usr/obj/usr/src/sys/SPAMKER
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Xeon(R) CPU           E3110  @ 3.00GHz (2999.68-MHz K8-class CPU)
  Origin = "GenuineIntel"  Id = 0x1067a  Stepping = 10
  Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
  Features2=0x408e3fd<SSE3,DTES64,MON,DS_CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,SSE4.1,XSAVE>
  AMD Features=0x20100800<SYSCALL,NX,LM>
  AMD Features2=0x1<LAHF>
  TSC: P-state invariant
real memory  = 4294967296 (4096 MB)
avail memory = 4119261184 (3928 MB)
ACPI APIC Table: <090208 APIC1432>
FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
FreeBSD/SMP: 1 package(s) x 2 core(s)
 cpu0 (BSP): APIC ID:  0
 cpu1 (AP): APIC ID:  1

For some reason that I still don't know, amavisd stop working, the
port no longer answer any inbound, postfix, spamd, clamd works,
amavisd is the issue normally.

My server can work for a month, each weekend I update the ports and
upgrade my packages, spamd rules every month are updated.

No issue here, suddenly after a month or 4-5 weeks the server stop
working, amavisd stop doing the job, I can access the server via ssh
and see the issue.

This is the 4th time that happens.

My IDLE goes to 50%, when I start debugging I see a process called
"FlowCleaner" eating 1 CPU.

Always got the PID 20, looks like a internal process, I have been
searching info about this process but not to much info.

I cannot kill this process, I can restart clamd, spamd, apache,
bacula, but amavisd is stuck.

If I send a shutdown -r now won't work, my server just hang-up, if I
press the power button won't work to.

I have to do a cold reboot, I don't have other choice.

I have read logs but don't see any issue (maillog, console, all, message).

One thing to mention, is that every time this happen, my server fan's
are working more faster that usual, the first day I detect this I
create a batch that send every 5 minutes the core temperature using
freebsd coretemp.ko module.

Avg. I got 40'c for each core:

dev.cpu.0.temperature: 42.0C
dev.cpu.1.temperature: 41.0C

I search around on Intel site and this chip max temp. is 70'c, I had
never seen this number on my emails, the biggest number had been 54'c
and this appear before my server got crazy yesterday:

dev.cpu.0.temperature: 53.0C
dev.cpu.1.temperature: 49.0C

Something is causing this, a spam attack, memory leak mmm I had not
seen my server use the whole 4GB ever.

My friends, what do u you recommend to me to track this?

Any input will be very appreciated, I got 1 month to track this before
this happen again, thanks!