On 2011-10-24, A C <agcarver+...@acarver.net> wrote: > On 10/24/2011 06:24, unruh wrote: >> On 2011-10-23, Uwe Klein<u...@klein-habertwedt.de> wrote: >>> A C wrote: >>>> More interesting is that the cpu was pegged until I was able to kill and >>>> restart ntpd. Most of the cpu was devoted to ntpd during this locked up >>>> period. Simple things like typing at the console were difficult. It >>>> would take a few seconds for a keypress to register on the screen. Once >>>> ntpd was restarted the system responded normally and the cpu usage >>>> dropped to normal levels. >>>> >>>> This is still version 4.2.6p3. I should probably go ahead and compile >>>> the most recently released version but I'm at a loss to understand why >>>> it happened. >>> >>> CPU (over)loaded >>> or the system is swapping like mad ? >> >> That would destroy everything ( ie slow everything to a crawl). Also >> ntpd is a small program and especially at heightened niceness (which he >> said he used) should not get swapped out or affected. >> >>> ( I'd think it is swapping? ) >>> > > Right, the swapping would only occur if I was trying to actively do > something while diagnosing the problem. Otherwise the system load is so > low there's no real need to swap. There is no desktop environment
? swapping occurs if system memory fills up completely and there is no more memory. It does not just refer to any disk access. Run top and see if there is a substantial swap useage. If there issomething is very wrong. > running on the system, only the standard daemons plus some extras (sshd, > ntpd, gpsd, crond, syslogd, inetd, postfix for system messages only) and > then one xterm (with ssh session inside) and one xclock. The cron jobs > are mostly system housekeeping (log rotation, etc.) that occur at 0:00 > but the crashes would occur at other times so none of the cron jobs were > running at the time of any crash. NOne of those would cause swapping unless you only have 1MB of memory. > > I've got extra RAM sticks that I pulled out during debugging in case I > had a bad memory cell but that turns out not to be the case so I'll need > to add all the sticks back in. Still the load isn't quite large enough > to swap everything out. Right now the machine is quiet and not swapping > anything unless I run something resource intensive. > > The header from top when things work normally (ntpd no longer running at > high priority in this capture): > >> load averages: 0.10, 0.09, 0.02; up 14+20:55:09 14:44:43 >> 22 processes: 21 sleeping, 1 on CPU >> CPU states: 10.5% user, 0.0% nice, 7.4% system, 6.4% interrupt, 75.8% idle >> Memory: 5048K Act, 2432K Inact, 300K Wired, 2316K Exec, 1336K File, 200K Free >> Swap: 128M Total, 9272K Used, 119M Free >> >> PID USERNAME PRI NICE SIZE RES STATE TIME WCPU CPU COMMAND >> 5738 root 85 0 5416K 1004K pause 19:25 0.24% 0.24% ntpd >> 0 root 125 0 0K 5608K cachegc 140:35 0.05% 0.05% [system] >> 410 agcarver 85 0 7328K 1212K select 27:54 0.05% 0.05% xterm >> 323 nobody 90 -10 13M 784K select 37.7H 0.00% 0.00% gpsd >> 533 agcarver 85 0 11M 728K select 106:58 0.00% 0.00% sshd >> 415 agcarver 85 0 7172K 676K select 94:31 0.00% 0.00% xclock _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
