Date: Sat, 27 Oct 2007 13:45:48 +0100 From: Bruce Cran <bruce@cran.org.uk> To: Gunther Mayer <gunther.mayer@googlemail.com> Cc: freebsd-questions@freebsd.org Subject: Re: CPU usage 100% but no process hogging CPU Message-ID: <472332FC.5040900@cran.org.uk> In-Reply-To: <47232945.10506@gmail.com> References: <47232945.10506@gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Gunther Mayer wrote: > Hi there, > > I'm having some capacity issues on the FreeBSD 6.2/Core 2 Duo/2GB RAM > server that I manage. For quite a few days now it constantly shows load > averages of around 1 and a CPU usage of around 100%. Yet summing up the > CPU usage of the individual processes running I hardly ever get to more > than 5%, regardless of how long I watch top. > > A snapshot of my top output looks like this: > > last pid: 96102; load averages: 1.28, 1.15, > 1.06 > up 22+08:33:16 13:55:03 > 122 processes: 2 running, 119 sleeping, 1 zombie > CPU states: 67.3% user, 0.0% nice, 32.7% system, 0.0% interrupt, 0.0% > idle > Mem: 474M Active, 974M Inact, 186M Wired, 68M Cache, 213M Buf, 93M Free > Swap: 4064M Total, 4064M Free > > PID USERNAME THR PRI NICE SIZE RES STATE TIME WCPU COMMAND > 635 root 1 122 0 27304K 2644K select 656:38 1.27% syslog-ng > 844 www 20 20 0 411M 300M kserel 360:13 0.00% java > 837 user1 3 20 0 29048K 5672K kserel 34:30 0.00% radiusd > 788 pgsql 1 96 0 13516K 3824K select 10:03 0.00% postgres > 785 pgsql 1 115 0 120M 7436K select 9:02 0.00% postgres > 787 pgsql 1 8 0 120M 41112K nanslp 5:15 0.00% postgres > > syslog-ng is quite busy as I use it to capture logs of more than 50 > remote sites. I have lots of slow queries in my postgres logs that I > think are related to this bottleneck, though unoptimised queries and an > ever growing amount of data are more likely to take the blame for that. > High disk I/O in this regard could explain the high system utilisation, > however. > > I found out that I've been bitten by the freebsd-update bug > (http://security.freebsd.org/advisories/FreeBSD-EN-07:05.freebsd-update.asc) > which replaced my SMP kernel with a GENERIC one and I'm taking > corrective action early tomorrow morning, but surely even with just a > single CPU the load average should never be as high? > > Where are those phantom CPU hogging processes? > By default top doesn't display system (kernel) processes, which can take up lots of CPU time. To show these, run top with the "-S" flag. -- Bruce
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?472332FC.5040900>