O_DIRECT, avoiding system cache?
mangoo at wpkg.org
Sat Mar 13 05:35:28 MST 2010
Is it possible (planned?) to make rsync avoid going through system cache
and use direct IO?
Right now, if you decide to backup your desktop system (but it's not
only about desktop systems; rather more about one-time-only data
transfers) to external disk, you will notice that your X session lags
terribly, mainly because:
- system caches everything what rsync reads from the original drive,
- system caches everything what rsync writes to the destination drive,
- while doing the above, current cache is being empties.
I've seen some discussions on rsync mailing list in the past about such
a feature (avoiding using system cache), but I'm not sure if there were
any conclusions out of it.
More information about the rsync