diff options
| author | bde <bde@FreeBSD.org> | 1995-12-29 15:30:05 +0000 |
|---|---|---|
| committer | bde <bde@FreeBSD.org> | 1995-12-29 15:30:05 +0000 |
| commit | 586cc683d875b37dce82c825feb9ccc7d884b35e (patch) | |
| tree | 9ce1e55534d3d930aead3ff55aeb7fcedbc086a4 /usr.sbin/kgmon/kgmon.8 | |
| parent | ff6f507f6bbb3fda77fb14c7201db37bafea7a3f (diff) | |
| download | FreeBSD-src-586cc683d875b37dce82c825feb9ccc7d884b35e.zip FreeBSD-src-586cc683d875b37dce82c825feb9ccc7d884b35e.tar.gz | |
Implemented non-statistical kernel profiling. This is based on
looking at a high resolution clock for each of the following events:
function call, function return, interrupt entry, interrupt exit,
and interesting branches. The differences between the times of
these events are added at appropriate places in a ordinary histogram
(as if very fast statistical profiling sampled the pc at those
places) so that ordinary gprof can be used to analyze the times.
gmon.h:
Histogram counters need to be 4 bytes for microsecond resolutions.
They will need to be larger for the 586 clock.
The comments were vax-centric and wrong even on vaxes. Does anyone
disagree?
gprof4.c:
The standard gprof should support counters of all integral sizes
and the size of the counter should be in the gmon header. This
hack will do until then. (Use gprof4 -u to examine the results
of non-statistical profiling.)
config/*:
Non-statistical profiling is configured with `config -pp'.
`config -p' still gives ordinary profiling.
kgmon/*:
Non-statistical profiling is enabled with `kgmon -B'. `kgmon -b'
still enables ordinary profiling (and distables non-statistical
profiling) if non-statistical profiling is configured.
Diffstat (limited to 'usr.sbin/kgmon/kgmon.8')
| -rw-r--r-- | usr.sbin/kgmon/kgmon.8 | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/usr.sbin/kgmon/kgmon.8 b/usr.sbin/kgmon/kgmon.8 index 114fea8..4a91582 100644 --- a/usr.sbin/kgmon/kgmon.8 +++ b/usr.sbin/kgmon/kgmon.8 @@ -39,7 +39,7 @@ .Nd generate a dump of the operating system's profile buffers .Sh SYNOPSIS .Nm kgmon -.Op Fl bhpr +.Op Fl Bbhpr .Op Fl M core .Op Fl N system .Sh DESCRIPTION @@ -62,8 +62,10 @@ file suitable for later analysis by .Pp The options are as follows: .Bl -tag -width Ds +.It Fl B +Resume the collection of high resolution profile data. .It Fl b -Resume the collection of profile data. +Resume the collection of low resolution profile data. .It Fl h Stop the collection of profile data. .It Fl p @@ -86,6 +88,8 @@ default ``/kernel''. .El .Pp If neither +.Fl B +nor .Fl b nor .Fl h @@ -96,6 +100,9 @@ flag is specified and profile data is being collected, profiling will be momentarily suspended, the operating system profile buffers will be dumped, and profiling will be immediately resumed. +.Pp +The profile buffers should be reset when the resolution +of the profile data is changed. .Sh FILES .Bl -tag -width /dev/kmemx -compact .It Pa /kernel |
