On Fri 09-11-12 15:12:43, Marcus Sundman wrote:On 09.11.2012 01:41, Marcus Sundman wrote:I was looking into the data but they didn't show anything problematic.On 07.11.2012 18:17, Jan Kara wrote:Here are some more vmstats:On Fri 02-11-12 04:19:24, Marcus Sundman wrote:t=01:06 http://sundman.iki.fi/vmstat.pre-freeze.txtAlso, and this might be important, according to iotop there isOK, it seems as if your machine has some problems with memory
almost no disk writing going on during the freeze. (Occasionally
there are a few MB/s, but mostly it's 0-200 kB/s.) Well, at least
when an iotop running on nice -20 hasn't frozen completely, which it
does during the more severe freezes.
allocations. Can you capture /proc/vmstat before the freeze and
after the
freeze and send them for comparison. Maybe it will show us what is the
system doing.
t=01:08 http://sundman.iki.fi/vmstat.during-freeze.txt
t=01:12 http://sundman.iki.fi/vmstat.post-freeze.txt
http://sundman.iki.fi/vmstats.tar.gz
They are from running this:
while true; do cat /proc/vmstat > "vmstat.$(date +%FT%X).txt"; sleep
10; done
There were lots and lots of freezes for almost 20 mins from 14:37:45
onwards, pretty much constantly, but at 14:56:50 the freezes
suddenly stopped and everything went back to how it should be.
The machine seems to be writing a lot but there's always some free memory,
even direct reclaim isn't ever entered. Hum, actually you wrote iotop isn't
showing much IO going on but vmstats show there is about 1 GB written
during the freeze. It is not a huge amount given the time span but it
certainly gives a few MB/s of write load.
There's surprisingly high number of allocations going on but that may be
due to the IO activity. So let's try something else: Can you switch to
console and when the hang happens press Alt-Sysrq-w (or you can just do
"echo w >/proc/sysrq-trigger" if the machine is live enough to do that).
Then send me the output from dmesg. Thanks!