Re: [PATCH] Remove OOM killer from try_to_free_pages / all_unreclaimable braindamage

On Friday, November 05, 2004 5:26 pm, Nick Piggin wrote:

quoted

If you move it in kswapd there's no way to prevent oom-killing from a
syscall allocation (I guess even right now it would go wrong in this
sense, but at least right now it's more fixable). I want to move the oom
kill outside the alloc_page paths. The oom killing is all about the page
faults not having a fail path, and in turn the oom killing should be
moved in the page fault code, not in the allocator. Everything else
should keep returning -ENOMEM to the caller.

Probably a good idea. OTOH, some kernel allocations might really
need to be performed and have no failure path. For example __GFP_REPEAT.

Ah, I see what you're saying, yes, that makes even more sense :)

I think maybe __GFP_REPEAT allocations at least should be able to
cause an OOM. Not sure though.

quoted

So to me moving the oom killer into kswapd looks a regression.

Also, I think it would do the wrong thing on NUMA machines because
that has a per-node kswapd.

Yep, Andrea's explaination is clear, I just had to read it a few times.  
Anyway, the fixes I posted are still necessary I think.

Thanks,
Jesse
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