B&R 10.1 Check Archive Integrity very quick

Using version 10.0 checking an archive used to take about 35 minutes now it only takes 10 minutes on the same size archive. Why the sudden dramatic speed up?

Have randomly extracted a few files from the backup and they seem ok. Is validity check reliable?

 

Just did my monthly diff backup and the diff archive was the same size as the base archive yet only a couple of files added. Verify integrity wizzed by in a second so obviously the archive is no good or the verify routing is rubbish as it has been since ver 9. I will now have to test with a restore. More time, never mind the increased almost doubling of the diff backup.

 

Do you defragment your system regularly? Since differential backups are sector based, defragmentation can cause the size of differential backups to grow disproportionately to the amount of data that was actually modified, since its location on the disk changes(i.e. the sectors change, even if the files don't). Over a short time it is quite possible that nearly all of the files on your system have been "defragmented" and have moved on the disk, causing a differential image to be as large as the base.

To avoid this, I recommend regularly recreating your base image, this will help keep the size of the differential images down.

 

Thanks for the tips. Yes I defragment once a month but it's a complete file sort so that may be why.

Doesn't explain why the Integrity check was over in seconds with no error.

Further thinking on my backup strategy leads me to think that maybe a full backup once a month is the way to go if diff backup uses sector information. I defrag quite regular so the backup map will change quite a lot and it may be faster to do it this way. Still cant understand why the integrity check is so unreliable. Was trying to save disk space but on large drives this is not going to work if the disk sector map has changed dramatically. Ho hum.