Commit Graph

10 Commits

Author SHA1 Message Date
Poul-Henning Kamp
cb3733b78d ARGH!
Pointy hat to:	phk
2003-03-18 17:05:27 +00:00
Poul-Henning Kamp
0d2fdd7850 Commit ken@' changes to this file: Bump version and append new entries
to stay backwards compatible.
2003-03-18 16:44:10 +00:00
Poul-Henning Kamp
36eab1f55a Add more devstat calculations, mostly filling in holes, but also adding
a couple of reqests:  DSM_BUSY_PCT and DSM_QUEUE_LENGTH.

I have no further plans for mutilating this API at this point in
time, and will update the man-page to reflect current reality as
the next thing.

Reviewed by:    ken
2003-03-18 09:57:54 +00:00
Poul-Henning Kamp
7194d335cf Run a revision of the devstat interface:
Kernel:

Change statistics to use the *uptime() timescale (ie: relative to
boottime) rather than the UTC aligned timescale.  This makes the
device statistics code oblivious to clock steps.

Change timestamps to bintime format, they are cheaper.

Remove the "busy_count", and replace it with two counter fields:
"start_count" and "end_count", which are updated in the down and
up paths respectively.  This removes the locking constraint on
devstat.

Add a timestamp argument to devstat_start_transaction(), this will
normally be a timestamp set by the *_bio() function in bp->bio_t0.
Use this field to calculate duration of I/O operations.

Add two timestamp arguments to devstat_end_transaction(), one is
the current time, a NULL pointer means "take timestamp yourself",
the other is the timestamp of when this transaction started (see
above).

Change calculation of busy_time to operate on "the salami principle":
Only when we are idle, which we can determine by the start+end
counts being identical, do we update the "busy_from" field in the
down path.  In the up path we accumulate the timeslice in busy_time
and update busy_from.

Change the byte_* and num_* fields into two arrays: bytes[] and
operations[].

Userland:

Change the misleading "busy_time" name to be called "snap_time" and
make the time long double since that is what most users need anyway,
fill it using clock_gettime(CLOCK_MONOTONIC) to put it on the same
timescale as the kernel fields.

Change devstat_compute_etime() to operate on struct bintime.

Remove the version 2 legacy interface: the change to bintime makes
compatibility far too expensive.

Fix a bug in systat's "vm" page where boot relative busy times would
be bogus.

Bump __FreeBSD_version to 500107

Review & Collaboration by:	ken
2003-03-15 21:59:06 +00:00
Kenneth D. Merry
c3508206b2 Turn on WARNS?= 2 for libdevstat.
Submitted by:	"Sergey A. Osokin" <osa@freebsd.org.ru>
2001-09-23 23:03:23 +00:00
Kenneth D. Merry
884539f701 Implement compute_stats() in terms of devstat_compute_statistics(). This
gets rid of the duplicated code in compute_stats().

Add a new DSM_SKIP statistic type for devstat_compute_statistics() that
causes the subsequent variable argument to be skipped.

Thanks to Sergey Osokin for coding up my idea/code fragment.

Submitted by:	"Sergey A. Osokin" <osa@freebsd.org.ru>
2001-08-18 05:46:59 +00:00
Thomas Moestl
c4a5ef6ef3 Add some features to libdevstat, and overhaul the interface a bit:
1.) prefix all functions in the library with devstat_ (compatability
    functions are available for all functions that were chaned in an
    incompatible way, but are deprecated).
2.) Add a pointer to a kvm_t as the first argument to functions that
    used to get their information via sysctl; they behave the same
    as before when NULL is passed as this argument, otherwise, the
    information is obtained via libkvm using the supplied handle.
3.) Add a new function, devstat_compute_statistics(), that is intended
    to replace the old compute_stats() function. It offers more
    statistics data, and has a more flexible interface.

libdevstat does now require libkvm; a library depedency is added, so
that libkvm only needs to be explicitely specified for statically linked
programs.
The library major version number is bumped.

Submitted by:	Sergey A. Osokin <osa@freebsd.org.ru>, ken (3)
Reviewed by:	ken
2001-08-04 18:25:48 +00:00
Peter Wemm
7f3dea244c $Id$ -> $FreeBSD$ 1999-08-28 00:22:10 +00:00
Kenneth D. Merry
bcc6a3da92 Change the devstat generation number from an int to a long. The int-sized
generation was causing unaligned access faults on the Alpha.

I have incremented the devstat version number, since this is an interface
change.  You'll need to recompile libdevstat, systat, iostat, vmstat and
rpc.rstatd along with your kernel.

Partially Submitted by:	Andrew Gallatin <gallatin@cs.duke.edu>
1998-09-20 00:11:23 +00:00
Justin T. Gibbs
28fb27ba21 Device statistics library. Used by iostat, vmstat, and systat to
format and analyze the output of the new device statistics sysctls.

Submitted by:	"Kenneth D. Merry" <ken@FreeBSD.org>
1998-09-15 06:23:21 +00:00