linux-sg2042/net
Chuck Lever ff8399709e SUNRPC: Replace jiffies-based metrics with ktime-based metrics
Currently RPC performance metrics that tabulate elapsed time use
jiffies time values.  This is problematic on systems that use slow
jiffies (for instance 100HZ systems built for paravirtualized
environments).  It is also a problem for computing precise latency
statistics for advanced network transports, such as InfiniBand,
that can have round-trip latencies significanly faster than a single
clock tick.

For the RPC client, adopt the high resolution time stamp mechanism
already used by the network layer and blktrace: ktime.

We use ktime format time stamps for all internal computations, and
convert to milliseconds for presentation.  As a result, we need only
addition operations in the performance critical paths; multiply/divide
is required only for presentation.

We could report RTT metrics in microseconds.  In fact the mountstats
format is versioned to accomodate exactly this kind of interface
improvement.

For now, however, we'll stay with millisecond precision for
presentation to maintain backwards compatibility with the handful of
currently deployed user space tools.  At a later point, we'll move to
an API such as BDI_STATS where a finer timestamp precision can be
reported.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14 15:09:33 -04:00
..
9p Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs 2010-04-05 13:42:54 -07:00
802 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
8021q 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
appletalk 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
atm 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
ax25 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
bluetooth bluetooth: handle l2cap_create_connless_pdu() errors 2010-04-27 17:03:36 -07:00
bridge bridge br_multicast: Ensure to initialize BR_INPUT_SKB_CB(skb)->mrouters_only. 2010-04-26 11:25:31 -07:00
can can: avoids a false warning 2010-04-13 03:03:14 -07:00
core veth: Dont kfree_skb() after dev_forward_skb() 2010-05-06 00:53:53 -07:00
dcb 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
dccp 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
decnet 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
dsa 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
econet 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
ethernet 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
ieee802154 ieee802154: Fix oops during ieee802154_sock_ioctl 2010-04-26 11:20:32 -07:00
ipv4 net: Fix FDDI and TR config checks in ipv4 arp and LLC. 2010-05-10 04:59:07 -07:00
ipv6 IPv6: fix IPV6_RECVERR handling of locally-generated errors 2010-05-05 21:32:40 -07:00
ipx 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
irda 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
iucv const: constify remaining dev_pm_ops 2009-12-15 08:53:25 -08:00
key 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
lapb 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
llc net: Fix FDDI and TR config checks in ipv4 arp and LLC. 2010-05-10 04:59:07 -07:00
mac80211 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6 2010-05-10 22:53:41 -07:00
netfilter 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
netlabel Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-04-06 08:34:06 -07:00
netlink Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-04-06 08:34:06 -07:00
netrom 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
packet packet : remove init_net restriction 2010-04-16 15:41:04 -07:00
phonet 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
rds rdma: potential ERR_PTR dereference 2010-04-22 15:57:26 -07:00
rfkill 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
rose 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
rxrpc 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
sched 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
sctp sctp: Fix a race between ICMP protocol unreachable and connect() 2010-05-06 00:56:07 -07:00
sunrpc SUNRPC: Replace jiffies-based metrics with ktime-based metrics 2010-05-14 15:09:33 -04:00
tipc 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
unix 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
wanrouter headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
wimax 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
wireless Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-04-06 08:34:06 -07:00
x25 X25 fix dead unaccepted sockets 2010-04-21 16:31:50 -07:00
xfrm 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
Kconfig net/compat/wext: send different messages to compat tasks 2009-07-15 08:53:39 -07:00
Makefile net: remove redundant sched/ in net/Makefile 2009-07-12 20:11:14 -07:00
TUNABLE
compat.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
nonet.c
socket.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
sysctl_net.c net: spread __net_init, __net_exit 2010-01-17 19:16:02 -08:00