Antoine wrote: > Hi, > > I use LVM (Linux Volume Manager) on my box. The MySQL datadir is mounted > on a specific ext3-formatted logical volume ; thus I am able to make live > snapshots of the database using the LVM snapshot fonctionnality. > Internally, LVM snapshots function by syncing the original partition to > disk and then backing up all further modified contents onto the snapshot > partition. So it is fast (creating the snapshot itself takes less than one > second), does not consume much disk (only changes are written to the snapshot > partition) and very convenient : one creates the snapshot, takes the time > to backup its contents onto a tape (or whatever), and then removes the > snapshot. All the while, the database is alive and can be written to by > MySQL without disturbing the backup. > > The question is : although the snapshot syncs the partition, is it sufficient > to guarantee that the data is in a consistent state ? That is, if it occurs > in the middle of a write by MySQL, will the MYD file be in good state or > may it be corrupted ? If consistency is not guaranteed, then I'll just > shutdown MySQL before creating the snapshot : this will make the database > unavailable for a few seconds - not a really big deal ;-). > > Does anyone already use this kind of setup ? Any comments about it ? > > Thank you > > Antoine. > Hi,
According to the documentation, you can use: FLUSH TABLES WITH READ LOCK for that. See http://www.mysql.com/doc/en/FLUSH.html for details Regards -- Joseph Beuno --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
