NAME    [Toc]    [Back]

       voliod  -  Starts,  stops,  and reports on Logical Storage
       Manager kernel I/O daemons

SYNOPSIS    [Toc]    [Back]

       /sbin/voliod

       /sbin/voliod [-f] set count

OPTIONS    [Toc]    [Back]

       Force the kill  of  the  last  I/O  daemon.  Without  this
       option,  the  I/O daemons can only be reduced to one.  See
       NOTES for an exception.

KEYWORDS    [Toc]    [Back]

       Sets the number of daemons to count.

DESCRIPTION    [Toc]    [Back]

       The voliod utility starts, stops, or  reports  on  Logical
       Storage  Manager kernel I/O daemons.  When invoked with no
       arguments, voliod prints the current number of volume  I/O
       daemons on the standard output.  When invoked with the set
       keyword, creates the number of daemons specified by count.
       If  more  volume  I/O  daemons exist than are specified by
       count, then the excess daemons will be terminated. If more
       than  the maximum number (64) are specified, the specified
       number will be silently limited to that maximum.

       The number of daemons necessary for general  I/O  handling
       depends  on system load and usage. One daemon for each CPU
       on the system (or a minimum of two) is generally adequate,
       unless volume recovery seems unusually slow.

       Each I/O daemon starts in the background, creates an asynchronously
 running kernel thread, and becomes a volume I/O
       daemon. The voliod utility does not wait for these threads
       to complete.

NOTES    [Toc]    [Back]

       Logical Storage Manager (LSM) automatically sets the  number
  of  I/O daemons when the system starts, so it is usually
 not necessary to set or change the number of I/O daemons
 with this command.

       On  systems  where the system attribute Max_LSM_IO_PERFORMANCE
 is set to 1 (default is 0), the  force  option  will
       not  allow you to kill the last daemon. You can reduce the
       number of daemons to 1 but not 0.  Attempts  to  kill  the
       last  daemon will result in an error message like the following,
 and will leave the number of daemons unchanged:  #
       voliod  -f  set  0  lsm:voliod:  ERROR:  VOL_IO_DAEMON_SET
       failed: Permission denied

       See sys_attrs_lsm(5) for more information.

       LSM I/O daemons cannot be stopped directly through the use
       of signals.

       The  number  of  Logical  Storage Manager I/O daemons currently
 running can be determined only by  running  voliod;
       I/O  daemons  do  not  appear  in  the  list  of processes
       produced by the ps(1) command.

EXIT CODES    [Toc]    [Back]

       The voliod utility displays a diagnostic on  the  standard
       error  and  exits  if  an  error is encountered. If an I/O
       error occurs within a spawned I/O daemon thread, then  the
       I/O is not reflected in the exit status for voliod. Otherwise,
 voliod returns a nonzero exit status on  errors,  as
       follows:  Usage  errors.  voliod displays a usage message.
       The requested number of daemons  cannot  be  started,  and
       voliod  reports the number that were successfully started.
       All other errors.

FILES    [Toc]    [Back]

       The device used to start and report on volume  I/O  daemon
       kernel threads.

SEE ALSO    [Toc]    [Back]

       Commands: vold(8), voldctl(8)

       Functions: fork(2), pthread(3)

       Other: sys_attrs_lsm(5), volintro(8)



                                                        voliod(8)