Messages in this thread Patch in this message | | | Date | Sat, 12 Dec 2009 18:25:22 -0800 | Subject | Re: nfs broken in net-next? -- now in mainline -- bisected: d9f5950f90292f7cc42834338dfd5f44dc4cc4ca | From | Yinghai Lu <> |
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On Sat, Dec 12, 2009 at 5:57 PM, Yinghai Lu <yinghai@kernel.org> wrote: > On Sat, Dec 12, 2009 at 5:05 PM, Yinghai Lu <yinghai@kernel.org> wrote: >> >> [f86dcc5aa8c7908f2c287e7a211228df599e3e71] udp: dynamically >> size hash tables at boot time > > commit f86dcc5aa8c7908f2c287e7a211228df599e3e71 > Author: Eric Dumazet <eric.dumazet@gmail.com> > Date: Wed Oct 7 00:37:59 2009 +0000 > > udp: dynamically size hash tables at boot time > > UDP_HTABLE_SIZE was initialy defined to 128, which is a bit small for > several setups. > > 4000 active UDP sockets -> 32 sockets per chain in average. An > incoming frame has to lookup all sockets to find best match, so long > chains hurt latency. > > Instead of a fixed size hash table that cant be perfect for every > needs, let UDP stack choose its table size at boot time like tcp/ip > route, using alloc_large_system_hash() helper > > Add an optional boot parameter, uhash_entries=x so that an admin can > force a size between 256 and 65536 if needed, like thash_entries and > rhash_entries. > > dmesg logs two new lines : > [ 0.647039] UDP hash table entries: 512 (order: 0, 4096 bytes) > [ 0.647099] UDP Lite hash table entries: 512 (order: 0, 4096 bytes) > > Maximal size on 64bit arches would be 65536 slots, ie 1 MBytes for non > debugging spinlocks. > > Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> > Signed-off-by: David S. Miller <davem@davemloft.net> > > cause the problem: nfs mount fail. > > the setup is: > 64bit kernel, have all needed drivers in kernel, and boot with > ip=dhcp, root disk is 256M ramdisk. > then try to mount nfs.... >
change entries default value from 65536 to 256, nfs mount will work.
YH
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 1f95348..57c13c3 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2054,7 +2054,7 @@ void udp4_proc_exit(void) } #endif /* CONFIG_PROC_FS */
-static __initdata unsigned long uhash_entries; +static __initdata unsigned long uhash_entries = UDP_HTABLE_SIZE_MIN; static int __init set_uhash_entries(char *str) { if (!str) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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