xlv_labd(7M)xlv_labd(7M)NAME
xlv_labd, xlv_plexd, xlvd - logical volume daemons
SYNOPSIS
xlv_labd
xlv_plexd [ -m #_subprocs ] [ -b blocksize ] [ -w sleep-interval ]
[ -v verbosity ] [ -h ]
DESCRIPTION
xlv_labd, xlv_plexd, and xlvd are logical volume daemons. xlv_labd and
xlv_plexd reside in user process space and xlvd resides in kernel process
space.
The XLV label daemon, xlv_labd, is a user process that writes logical
volume disk labels. It is normally started during system restart. Upon
startup, xlv_labd immediately calls into the kernel to wait for an action
request from the kernel daemon, xlvd. When an action request comes,
xlv_labd processes it and updates the appropriate volume disk labels.
After completing the update, xlv_labd calls back into the kernel to wait
for another request.
The XLV plex copy daemon, xlv_plexd, is a user process responsible for
making all plexes within a subvolume consistent. The master xlv_plexd
process is started at system startup time with the -m option and
subsequently used when new plexes are added. It receives requests to
revive plexes via the named pipe /etc/.xlv_plexd_request_fifo and starts
child processes to perform the actual plex copy.
-m #_subprocs #_subprocs is the maximum number of subprocesses the
master xlv_plexd process forks off at any given time.
-b blocksize blocksize is the granularity of a single plex copy
operation in blocks. The default is 128 blocks,
which means XLV initiates a plex copy of 128 blocks,
sleeps as indicated by the -w option (see below),
then moves on to the next set of 128 blocks.
-w sleep-interval sleep-interval is an arbitrary delay enforced at
regular intervals while performing a plex copy in
order to share available disk bandwidth. The default
delay is 0.
-v verbosity verbosity is the level of verbosity. The minimum is
0 and the maximum is 3. xlv_plexd writes its
messages to syslog. The default verbosity is 2.
-h Print the help message.
The XLV daemon, xlvd, is a kernel process that handles I/O to plexes and
performs plex error recovery. When disk labels require updating, xlvd
initiates an action request to xlv_labd to perform the disk label update.
If there aren't multiple plexes, xlvd does not do anything.
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xlv_labd(7M)xlv_labd(7M)NOTE
All three daemons are automatically started and do not need to be
explicitly invoked.
FILES
/etc/.xlv_plexd_request_fifo
SEE ALSOxlv(7M).
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