Peter's Blog

Since plugging Cobian Backup last week I have noticed that it leaves two processes running all the time, committing about 15M of memory, 7M of it for a UI to support a status icon, the rest for the backup service. Since the backup only runs once a day for a minute or so I don't see the point of committing resources all the time: the Windows scheduler service is running all the time anyway, so why run another service to do backups?

I've written a new batch file to do a rolling backup using 7zip, a very nice compression package:

rem
rem yet  another backup script
rem
erase "%2\Backup9.7z"
move "%2\Backup8.7z" "%2\Backup9.7z"
move "%2\Backup7.7z" "%2\Backup8.7z"
move "%2\Backup6.7z" "%2\Backup7.7z"
move "%2\Backup5.7z" "%2\Backup6.7z"
move "%2\Backup4.7z" "%2\Backup5.7z"
move "%2\Backup3.7z" "%2\Backup4.7z"
move "%2\Backup2.7z" "%2\Backup3.7z"
move "%2\Backup.7z" "%2\Backup2.7z"

"c:\program files\7-zip\7z" a -r -x@"c:\bin\exclude.txt" "%2\Backup.7z" "%1\*

Exclude.txt is a list of file extensions that should not be backed up.

A wrapper batch file is created to call the above for each backup source:

c:\bin\backup c:\desktop g:\backup\desktop

and this wrapper is run from the Windows scheduler.

I am using 7zip because of the way it allows a source directory to be specified: I'm not sure regular info-zip supports this so cleanly.

7Zip native zip format creates smaller archive files than regular zip (albeit more slowly) and yet salamander still allows me to view them like regular directories so for me there is no practical difference between zip and 7zip. 7zip can be told to create regular zip files is need be.

7Zip supports incremental backups and if my backup files became very large I would consider using it but the external hard disk that I backup to is 80G and has space aplenty so there isn't much to be gained from this.