Hi,
Tried your patch on 2.2.4-test9-pre4
with the included debug patch applied.
Rebooted, started mmap002
After a while it starts outputting (magic did not work
this time - usually does):
- - -
"VM: try_to_free_pages (result: 1) try_again # 12345"
"VM: try_to_free_pages (result: 1) try_again # 12346"
- - -
My interpretation:
1) try_to_free_pages succeeds (or returns ok when it did not work)
2) __alloc_pages still can't alloc
Maybe it is different limits,
try_to_free_pages requires less to succeed than
__alloc_pages_limit requires.
or a bug in
__alloc_pages_limit(zonelist, order, PAGES_MIN, direct_reclaim)
Note:
12345 is an example, it loops to over 30000...
/RogerL
Rik van Riel wrote:
>
> Hi,
>
> I've found and fixed the deadlocks in the new VM. They turned out
> to be single-cpu only bugs, which explains why they didn't crash my
> SMP tesnt box ;)
>
> They have to do with the fact that processes schedule away while
> holding IO locks after waking up kswapd. At that point kswapd
> spends its time spinning on the IO locks and single-cpu systems
> will die...
>
> Due to bad connectivity I'm not attaching this patch but have only
> put it online on my home page:
>
> http://www.surriel.com/patches/2.4.0-t9p2-vmpatch
>
> (yes, I'm at a conference now ... the worst beating this patch
> has had is a full night in 'make bzImage' with mem=8m)
>
> regards,
>
> Rik
> --
> "What you're running that piece of shit Gnome?!?!"
> -- Miguel de Icaza, UKUUG 2000
>
> http://www.conectiva.com/ http://www.surriel.com/
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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> Please read the FAQ at http://www.tux.org/lkml/
-- Home page: http://www.norran.net/nra02596/
--- mm/page_alloc.c.orig Thu Sep 21 20:02:54 2000 +++ mm/page_alloc.c Thu Sep 21 20:49:35 2000 @@ -295,6 +295,7 @@ int direct_reclaim = 0; unsigned int gfp_mask = zonelist->gfp_mask; struct page * page = NULL; + int try_again_loops = 0; /* * Allocations put pressure on the VM subsystem. @@ -320,8 +321,10 @@ /* * Are we low on inactive pages? */ - if (inactive_shortage() > inactive_target / 2 && free_shortage()) + if (inactive_shortage() > inactive_target / 2 && free_shortage()) { + printk("VM: inactive shortage wake kswapd\n"); wakeup_kswapd(0); + } try_again: /* @@ -410,6 +413,7 @@ * piece of free memory. */ if (order > 0 && (gfp_mask & __GFP_WAIT)) { + printk("VM: higher order"); zone = zonelist->zones; /* First, clean some dirty pages. */ page_launder(gfp_mask, 1); @@ -444,7 +448,9 @@ * processes, etc). */ if (gfp_mask & __GFP_WAIT) { - try_to_free_pages(gfp_mask); + int success = try_to_free_pages(gfp_mask); + printk("VM: try_to_free_pages (result: %d) try_again # %d\n", + success, ++try_again_loops); memory_pressure++; goto try_again; }
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sat Sep 23 2000 - 21:00:25 EST