NAME
vxiod — start, stop, and report on Volume Manager kernel daemons
SYNOPSIS
vxiod
vxiod
[-f ]
[set count]
DESCRIPTION
The vxiod utility starts, stops, or reports on Volume Manager
I/O daemons. An I/O daemon provides a process
context for performing Volume Manager I/O.
Volume Manager I/O daemons are not required for
correct operation, but not having I/O daemons can
adversely affect system performance.
When invoked with no arguments,
vxiod
prints the current number of volume I/O daemons on the standard
output.
The number of daemons to
create for general I/O handling is dependent on system load and usage.
If volume recovery seems to proceed slower at times,
it may be worthwhile to create more daemons.
Each I/O daemon starts in the background
and creates an asynchronously-running process, which detaches itself
from the controlling terminal and becomes a volume I/O daemon. The
vxiod
utility does not wait for these processes to complete.
KEYWORDS
- set
When invoked with the
set
keyword,
vxiod
creates
the number of daemons specified by
count.
If more volume I/O daemons exist than are specified by
count,
the excess processes terminate.
If more than the maximum number (64) are created,
the requested number is silently
truncated to that maximum.
OPTIONS
- -f
Forcibly kills the last I/O daemon.
Without this option, the number of I/O
daemons cannot be reduced to zero.
EXIT CODES
The
vxiod
utility prints a diagnostic on the standard error, and exits if an
error is encountered. If an I/O occurs within a forked I/O daemon
process, then the I/O is not reflected in the exit status for
vxiod.
Otherwise,
vxiod
returns a non-zero exit status on errors.
Usage errors result in an exit status of 1 and a usage message. If
the requested number of daemons cannot be created, then the exit
status is 2, and the number of daemons that
were successfully started is
reported. If any other error occurs, the exit status is 3.
FILES
- /dev/vx/iod
The device used to report on and start volume I/O daemon processes.
NOTES
Volume Manager I/O daemons cannot be killed directly through the
use of signals.
The number of Volume Manager I/O daemons currently running can only be
determined by running vxiod; I/O daemons do not appear in the
list of processes produced by the ps command.
Printable version
