APMD(8) | System Manager's Manual | APMD(8) |
apmd
— Advanced
Power Management daemon
apmd |
[-AadHLs ] [-f
devname] [-S
sockname] [-t
seconds] [-Z
percent] [-z
percent] |
apmd
monitors the advanced power
management device, apm(4),
acting on signaled events and upon user requests as sent by the
apm(8) program.
For suspend and standby request events delivered by the BIOS, or
via apm(8),
apmd
runs the appropriate configuration program (if
one exists), syncs the buffer cache to disk and initiates the requested
state. When resuming after suspend or standby, apmd
runs the appropriate configuration program (if one exists).
When the power status changes (battery is connected or
disconnected), apmd
fetches the current status and
reports it via syslog(3) with
logging facility LOG_DAEMON
.
The options are as follows:
-A
apmd
in automatic performance adjustment
mode (the default).-a
-d
apmd
enters debug mode, staying in the foreground.
Logging output is printed to stderr.-f
devname-H
apmd
in manual performance adjustment mode,
initialising hw.setperf to 100.-L
apmd
in manual performance adjustment mode,
initialising hw.setperf to 0.-S
sockname-s
apmd
exits without monitoring the APM status.-t
secondsapmd
periodically polls the APM driver for the
current power state. If the battery charge level changes substantially or
the external power status changes, the new status is logged. The polling
rate defaults to once per 10 minutes, but may be specified using the
-t
command-line flag.-Z
percent-z
percentIf both -Z
and
-z
are specified, the last one will supersede
the other. After a resume, the effect of those options is inhibited for
60 seconds.
When a client requests a suspend or stand-by state,
apmd
does not wait for positive confirmation that
the requested state has been entered before replying to the client; to do so
would mean the client does not get a reply until the system resumes from its
sleep state. Rather, apmd
replies with the intended
state to the client and then places the system in the requested state after
running the configuration script and flushing the buffer cache.
Actions can be configured for the following transitions: suspend,
hibernate, standby, resume, powerup, and powerdown. The suspend, hibernate
and standby actions are run prior to apmd
performing
any other actions (such as disk syncs) and entering the new state. The
resume program is run after resuming from a stand-by or suspended state. The
powerup and powerdown programs are run after the power status (AC connected
or not) changes, as well as after a resume (if the power status changed in
the mean time).
syslog(3), apm(4), apm(8), sysctl(8)
Advanced Power Management (APM) BIOS Interface Specification (revision 1.2), Intel Corporation and Microsoft Corporation.
The apmd
command first appeared in
NetBSD 1.3. OpenBSD support
was added in OpenBSD 1.2.
March 31, 2022 | OpenBSD-7.1 |