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| author | Scott Mayhew <smayhew@redhat.com> | 2015-04-29 17:38:26 +0300 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2015-05-04 19:02:44 +0300 |
| commit | 72faedae8bc3504ee4252cebf14737a23677cb8f (patch) | |
| tree | 54b8cf6952635e1d1f287527fe5cd984b42717a4 /Documentation/filesystems | |
| parent | fd891454609ec036dc23e34536e45d655b4ca4db (diff) | |
| download | linux-72faedae8bc3504ee4252cebf14737a23677cb8f.tar.xz | |
Documentation: remove overloads-avoided counter from knfsd-stats.txt
The 'overloads-avoided' counter itself was removed several years ago by
commit 78c210e (Revert "knfsd: avoid overloading the CPU scheduler with
enormous load averages").
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/nfs/knfsd-stats.txt | 44 |
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 |