linux/net/unix
Eric Dumazet eb6a24816b af_unix: reduce high order page allocations
unix_dgram_sendmsg() currently builds linear skbs, and this can stress
page allocator with high order page allocations. When memory gets
fragmented, this can eventually fail.

We can try to use order-2 allocations for skb head (SKB_MAX_ALLOC) plus
up to 16 page fragments to lower pressure on buddy allocator.

This patch has no effect on messages of less than 16064 bytes.
(on 64bit arches with PAGE_SIZE=4096)

For bigger messages (from 16065 to 81600 bytes), this patch brings
reliability at the expense of performance penalty because of extra pages
allocations.

netperf -t DG_STREAM -T 0,2 -- -m 16064 -s 200000
->4086040 Messages / 10s

netperf -t DG_STREAM -T 0,2 -- -m 16068 -s 200000
->3901747 Messages / 10s

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-03 16:43:18 -04:00
..
af_unix.c af_unix: reduce high order page allocations 2012-04-03 16:43:18 -04:00
diag.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-03-21 13:36:41 -07:00
garbage.c Allow passing O_PATH descriptors via SCM_RIGHTS datagrams 2011-03-15 02:21:45 -04:00
Kconfig net: Default UDP and UNIX diag to 'n'. 2012-01-07 12:13:06 -08:00
Makefile unix_diag: Write it into kbuild 2011-12-16 13:48:29 -05:00
sysctl_net_unix.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00