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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-27 10:14:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-27 10:14:39 -0700
commitd2c3ac7e7e39ec6d37e4114ae7444948561e59af (patch)
treec0e6a9eed0139de4e757fbf64498fe8c0b291e44 /Documentation/filesystems
parent546fac60739ef8d7cbf8ce0b8251a519f68b2804 (diff)
parent901f1379f6c9dc2d73b51971d129a6f7d5b9b20a (diff)
Merge branch 'for-4.2' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields: "A relatively quiet cycle, with a mix of cleanup and smaller bugfixes" * 'for-4.2' of git://linux-nfs.org/~bfields/linux: (24 commits) sunrpc: use sg_init_one() in krb5_rc4_setup_enc/seq_key() nfsd: wrap too long lines in nfsd4_encode_read nfsd: fput rd_file from XDR encode context nfsd: take struct file setup fully into nfs4_preprocess_stateid_op nfsd: refactor nfs4_preprocess_stateid_op nfsd: clean up raparams handling nfsd: use swap() in sort_pacl_range() rpcrdma: Merge svcrdma and xprtrdma modules into one svcrdma: Add a separate "max data segs macro for svcrdma svcrdma: Replace GFP_KERNEL in a loop with GFP_NOFAIL svcrdma: Keep rpcrdma_msg fields in network byte-order svcrdma: Fix byte-swapping in svc_rdma_sendto.c nfsd: Update callback sequnce id only CB_SEQUENCE success nfsd: Reset cb_status in nfsd4_cb_prepare() at retrying svcrdma: Remove svc_rdma_xdr_decode_deferred_req() SUNRPC: Move EXPORT_SYMBOL for svc_process uapi/nfs: Add NFSv4.1 ACL definitions nfsd: Remove dead declarations nfsd: work around a gcc-5.1 warning nfsd: Checking for acl support does not require fetching any acls ...
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r--Documentation/filesystems/nfs/knfsd-stats.txt44
1 files changed, 4 insertions, 40 deletions
diff --git a/Documentation/filesystems/nfs/knfsd-stats.txt b/Documentation/filesystems/nfs/knfsd-stats.txt
index 64ced5149d37..1a5d82180b84 100644
--- a/Documentation/filesystems/nfs/knfsd-stats.txt
+++ b/Documentation/filesystems/nfs/knfsd-stats.txt
@@ -68,16 +68,10 @@ sockets-enqueued
rate of change for this counter is zero; significantly non-zero
values may indicate a performance limitation.
- This can happen either because there are too few nfsd threads in the
- thread pool for the NFS workload (the workload is thread-limited),
- or because the NFS workload needs more CPU time than is available in
- the thread pool (the workload is CPU-limited). In the former case,
- configuring more nfsd threads will probably improve the performance
- of the NFS workload. In the latter case, the sunrpc server layer is
- already choosing not to wake idle nfsd threads because there are too
- many nfsd threads which want to run but cannot, so configuring more
- nfsd threads will make no difference whatsoever. The overloads-avoided
- statistic (see below) can be used to distinguish these cases.
+ This can happen because there are too few nfsd threads in the thread
+ pool for the NFS workload (the workload is thread-limited), in which
+ case configuring more nfsd threads will probably improve the
+ performance of the NFS workload.
threads-woken
Counts how many times an idle nfsd thread is woken to try to
@@ -88,36 +82,6 @@ threads-woken
thing. The ideal rate of change for this counter will be close
to but less than the rate of change of the packets-arrived counter.
-overloads-avoided
- Counts how many times the sunrpc server layer chose not to wake an
- nfsd thread, despite the presence of idle nfsd threads, because
- too many nfsd threads had been recently woken but could not get
- enough CPU time to actually run.
-
- This statistic counts a circumstance where the sunrpc layer
- heuristically avoids overloading the CPU scheduler with too many
- runnable nfsd threads. The ideal rate of change for this counter
- is zero. Significant non-zero values indicate that the workload
- is CPU limited. Usually this is associated with heavy CPU usage
- on all the CPUs in the nfsd thread pool.
-
- If a sustained large overloads-avoided rate is detected on a pool,
- the top(1) utility should be used to check for the following
- pattern of CPU usage on all the CPUs associated with the given
- nfsd thread pool.
-
- - %us ~= 0 (as you're *NOT* running applications on your NFS server)
-
- - %wa ~= 0
-
- - %id ~= 0
-
- - %sy + %hi + %si ~= 100
-
- If this pattern is seen, configuring more nfsd threads will *not*
- improve the performance of the workload. If this patten is not
- seen, then something more subtle is wrong.
-
threads-timedout
Counts how many times an nfsd thread triggered an idle timeout,
i.e. was not woken to handle any incoming network packets for