xtrabackup prepare - after dump or before restore? i have doubts about xtrabackup --apply-log.
is there any difference when use it? should it be done right after dump or before restore (even few months later)? seems stupid, but maybe i missing something.

documentation says this:


  Prepare a backup in BACKUP-DIR by applying the transaction log file named xtrabackup_logfile located in the same directory. Also, create new transaction logs. The InnoDB configuration is read from the file backup-my.cnf created by innobackupex when the backup was made.


thanks for help :)
The chief reason to use --apply-log until the time of restore is to support incremental backups.  

If you make incremental backups, you would use --apply-log --redo-only each incremental backup, and then just before you restore, you do a final prepare with --apply-log.

Otherwise if you don't make incremental backups, there's no reason not to do --apply-log right after you make the back up.  Then it's ready to restore on a moment's notice.