Re: 2.4.0-t9p7 and mmap002 - freeze
From: Mike Galbraith <hidden>
Date: 2000-09-28 06:31:56
On Wed, 27 Sep 2000, Roger Larsson wrote:
Hi, Tried latest patch with the same result - freeze...
Ditto.
No extra patches added.
Ditto.
running from console as root mmap002 from memtest-0.0.3 with RAMSIZE defined as 90 MB (I have 96MB) after a while with heavy disk access (thrashing?) the drive becomes silent - no more progress... [if you can not repeat this - try with less memory 32 MB...]
I'm using a little proggy from Christoph Rohland (swptst.c), and do not have to jump through any hoops to reproduce the freeze.
Magic works! Magic memory Constantly LOW on inactive_clean (0 is the most common) lots of shared memory (almost equals active) [can be normal condition since mmap002 produces dirty mmaped pages] Magic process: Manual samples gave the following locations. (NOTE: not a call trace)
If a kdb call trace will help (doubt it.. see below) I can post one.
We are trying to clean pages, but do we make any progress since disk is silent? Trace; c0127d85 <page_launder+3d/724> Trace; c0126dad <deactivate_page_nolock+13d/248> Trace; c0127e00 <page_launder+b8/724> Trace; c0128035 <page_launder+2ed/724> Trace; c0127dcc <page_launder+84/724> Trace; c0127dd0 <page_launder+88/724> Trace; c0127e00 <page_launder+b8/724> Trace; c012fd38 <try_to_free_buffers+4/138> Magic Sigterm (Alt+SysRq+E) Gives you a running system again.
Not here. I looked at it with an IKD kernel, and here it's the same loop as before.. __alloc_pages() running through try_again forever. inactive_clean=0, a few pages bouncing between active and inactive_dirty. __switch_to() never happens. (though I can artificially yield and thus make sysrq-e work. Artificially scheduling only ensures that all other tasks loop the same way. [coz inactive_clean=0.. page_launder() is always failing to find something freeable])
Notes: Probably timing critical for entry into this state since adding a few printk:s makes it happen less often. I have even got complete mmap002 runs succeed - but disk is running too much and for too long time... a lot more than 10 min - normal run on previous testX did usually take less than 3 minutes.
I'm still at < 1 minute survival.. with many seconds to spare ;-) I have yet to have a run succeed, though virgin source _does_ last a bit longer (odd) than KDB enabled kernel. -Mike -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/