Heavy system load by pagedaemon

[Dan Nelson]

In the last episode (May 10), Iasen Kostov said:
> On Wed, 2006-05-10 at 15:32 +0300, Iasen Kostov wrote:
> > On Wed, 2006-05-10 at 15:28 +0300, Iasen Kostov wrote:
> > > I (probably) have some problem with a hosting server machine
> > > halting about once a 30 to minute (probably when the free memory
> > > falls under some threshold). At that moment the machine totally
> > > halts for about 5 sec then resumes normal work with load average
> > > around 9-15 (depends on system load) from about 2-3. The system
> > > is:
> > > (nice try :()
> >  FreeBSD 6.1-PRERELEASE #7: Wed Mar 15 17:35:21 EET 2006
> > 
> >  ACPI APIC Table: <PTLTD          APIC  >
> >  Timecounter "i8254" frequency 1193182 Hz quality 0
> >  CPU: Dual Core AMD Opteron(tm) Processor 270 (2004.56-MHz K8-class CPU)
> >    Origin = "AuthenticAMD"  Id = 0x20f12  Stepping = 2
> > 
> > Features=0x178bfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,MMX,FXSR,SSE,SSE2,HTT>
> >    Features2=0x1<SSE3>
> >    AMD Features=0xe2500800<SYSCALL,NX,MMX+,<b25>,LM,3DNow+,3DNow>
> >  real memory  = 8724152320 (8320 MB)
> >  avail memory = 8315379712 (7930 MB)
> >  FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
> > 
> 	Hum, I was probably wrong about the free memory threshold - it
> currently has ~1600MB of free and it is doing it again. When the free
> memory falls under ~30MB it is just doing it more frequently.

Are you swapping?  Paste in the output "top -o size".  If you have
processes that are in the 1gb range, then when one exits you will end
up with a lot of "free" memory for a short period of time, and it may
try paging in another process that was completely paged out (if you are
low enough on RAM for that to have happened).  That could cause
pagedaemon activity.

-- 
	Dan Nelson
	dnelson at allantgroup.com