On Sat, 2006-08-12 at 14:42 +0400, Evgeniy Polyakov wrote:

When network uses the same allocator, it depends on it, and thus it is
possible to have (cut by you) a situation when reserve (which depends on
SLAB and it's OOM too) is not filled or even does not exist.

No, the reserve does not depend on SLAB, and I totally short-circuit the
SLAB allocator for skbs and related on memory pressure.

The memalloc reserve is on the page allocator level and is only
accessable for PF_MEMALLOC processes or __GFP_MEMALLOC (new in my
patches) allocations. (arguably there could be some more deadlocks wrt.
PF_MEMALLOC where the code under PF_MEMALLOC is not properly bounded,
those would be bugs and should be fixed if present/found)

If transferred to your implementation, then just steal some pages from
SLAB when new network device is added and use them when OOM happens.
It is much simpler and can help in the most of situations.

SLAB reclaim is painfull and has been tried by the time you OOM.