Re: 2.6.20-rc5: cp 18gb 18gb.2 = OOM killer, reproducible just like2.16.19.2

From: Bill Cizek
Date: Wed Jan 24 2007 - 20:28:38 EST


Justin Piszcz wrote:
On Mon, 22 Jan 2007, Andrew Morton wrote:
On Sun, 21 Jan 2007 14:27:34 -0500 (EST) Justin Piszcz <jpiszcz@xxxxxxxxxxxxxxx> wrote:
Why does copying an 18GB on a 74GB raptor raid1 cause the kernel to invoke the OOM killer and kill all of my processes?
Running with PREEMPT OFF lets me copy the file!! The machine LAGS occasionally every 5-30-60 seconds or so VERY BADLY, talking 5-10 seconds of lag, but hey, it does not crash!! I will boot the older kernel with preempt on and see if I can get you that information you requested.
Justin,

According to your kernel_ring_buffer.txt (attached to another email), you are using "anticipatory" as your io scheduler:
289 Jan 24 18:35:25 p34 kernel: [ 0.142130] io scheduler noop registered
290 Jan 24 18:35:25 p34 kernel: [ 0.142194] io scheduler anticipatory registered (default)

I had a problem with this scheduler where my system would occasionally lockup during heavy I/O. Sometimes it would fix itself, sometimes I had to reboot. I changed to the "CFQ" io scheduler and my system has worked fine since then.

CFQ has to be built into the kernel (under BlockLayer/IOSchedulers). It can be selected as default or you can set it during runtime:

echo cfq > /sys/block/<disk>/queue/scheduler
...

Hope this helps,
Bill
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/