mirror of https://gitee.com/openkylin/linux.git
529bf6be5c
I have benchmarked this on an x86_64 NUMA system and see no significant performance difference on kernbench. Tested on both x86_64 and powerpc. The way we do file struct accounting is not very suitable for batched freeing. For scalability reasons, file accounting was constructor/destructor based. This meant that nr_files was decremented only when the object was removed from the slab cache. This is susceptible to slab fragmentation. With RCU based file structure, consequent batched freeing and a test program like Serge's, we just speed this up and end up with a very fragmented slab - llm22:~ # cat /proc/sys/fs/file-nr 587730 0 758844 At the same time, I see only a 2000+ objects in filp cache. The following patch I fixes this problem. This patch changes the file counting by removing the filp_count_lock. Instead we use a separate percpu counter, nr_files, for now and all accesses to it are through get_nr_files() api. In the sysctl handler for nr_files, we populate files_stat.nr_files before returning to user. Counting files as an when they are created and destroyed (as opposed to inside slab) allows us to correctly count open files with RCU. Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
||
---|---|---|
.. | ||
802 | ||
8021q | ||
appletalk | ||
atm | ||
ax25 | ||
bluetooth | ||
bridge | ||
core | ||
dccp | ||
decnet | ||
econet | ||
ethernet | ||
ieee80211 | ||
ipv4 | ||
ipv6 | ||
ipx | ||
irda | ||
key | ||
lapb | ||
llc | ||
netfilter | ||
netlink | ||
netrom | ||
packet | ||
rose | ||
rxrpc | ||
sched | ||
sctp | ||
sunrpc | ||
tipc | ||
unix | ||
wanrouter | ||
x25 | ||
xfrm | ||
Kconfig | ||
Makefile | ||
TUNABLE | ||
compat.c | ||
nonet.c | ||
socket.c | ||
sysctl_net.c |