By default, a periodic sync is set to run once a week on Sundays at midnight. You can change that to be any time you like, running it as often as once a day. The times are recorded in the following file:
Periodic syncs are managed by the
dblogd(8) process. At the time of the
sync, the running
dblogd(8) process spawns a child. The child
dblogd(8) manages the synchronization actions. For every event that requires an update to the database, the child
dblogd(8) spawns its own child. The “grandchild” process dies when the event has been given to
mysqld. The “child” process dies when the
sync is complete. While a periodic
sync is happening, you will see a parent
dblogd(8), a child
dblogd(8), and possibly a grandchild
dblogd(8) with a very short life span.
A periodic sync affects all enabled volumes; you can’t specify volumes you don’t want
synced.
Periodic syncs are similar to running a
syncvoltodb path_to_volume;
for example,. a
sync with no flags. For more details on the
-delnorm flag, see
"Syncs: to -delnorm or not to -delnorm” on page 638. In effect, this means that the
sync done periodically is less thorough (but much quicker) than a
sync done with the
-delnorm option.
Every periodic sync will cause the
venture.log file to be moved to
venture.log.old. A new
venture.log is not created immediately, but rather when the need to log something arises. In other words, you may not see a
venture.log file after a periodic
sync.
The main purpose of running a periodic sync is to catch minor discrepancies between the file system and the database that were not caught by
dblogd(8) or
listdir. Note that periodic
syncs will not catch every type of discrepancy. In those cases, a
sync using one of the -
delnorm options is more appropriate.
