Date: Mon, 17 Feb 2003 12:57:26 -0500 From: Bill Moran <wmoran@potentialtech.com> To: Roman Neuhauser <neuhauser@bellavista.cz> Cc: freebsd-questions <freebsd-questions@freebsd.org> Subject: Re: processes take too much CPU Message-ID: <3E512286.6010803@potentialtech.com> References: <20030217143524.GA81356@freepuppy.bellavista.cz>
next in thread | previous in thread | raw e-mail | index | archive | help
Roman Neuhauser wrote: > I have a problem with on of my FreeBSD boxes. All of a sudden, it > started acting very badly: any process takes ages to start completely, > eating all CPU in the process: > > PID USERNAME PRI NICE SIZE RES STATE TIME WCPU CPU COMMAND > 852 root 57 0 1528K 996K RUN 0:19 91.95% 59.81% top > > root@ishtar ~ 1017:0 # time ps auxww > ... > ps auxww 0.00s user 0.01s system 0% cpu 2.197 total > root@ishtar ~ 1018:0 # Looks like it's not eating up much of the computer's time to start, just that something else is preventing it from accessing what it wants immediately. Could be starved from RAM, or waiting on a busy ATA controller or any number of things. > compare a slower box: > > root@lilith ~ 1005:0 # time ps auxww > ps auxww 0.00s user 0.02s system 64% cpu 0.036 total > root@lilith ~ 1006:0 # Sounds like the faster box is bogged down with some task. Maybe flushing disk data? What else is running on this box? > This strangeness lasted for about 20 minutes, persisted across a reboot > (I pulled out the wrong cable...), and then just disappeared; the box > works as it should. You don't state the hardware either. Lots of places a bottleneck could occur that would make the system sluggish. > I know this is hard to asnwer, but what could have caused the effect, > and what should I be looking for if it happens again? There's nothing > especially interesting in /var/log/messages. I've seen some processes suddenly grab a lot of the machine's ability and bog it down temporarily. Usually with a combination of top and systat, I can identify where the load is coming from. This is especially noticable in 5.0. You don't say, but I'm assuming you're running 4.x though. > BTW, top showed swap wasn't used at all. Out of ram/swapping isn't the only place a machine can bog down. What applications are you running on it? Does top show any other processes using a lot of CPU time? A snapshot of top output while the problem is occurring would be informational to anyone trying to help. -- Bill Moran Potential Technologies http://www.potentialtech.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3E512286.6010803>