Backup-File sizes not as expected

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Markus
Posts: 28
Joined: Sat Oct 19, 2002 7:34 pm

Backup-File sizes not as expected

Post by Markus »

Hi Barry,
I´m wondering if the setting for maximum file-size in a backup-job is working correctly. I have a configuration backing up to a a local disk-drive. The Backup-Job ist configured with

max. backup-file-size 50 MB
max. number of files 2500

On the initial backup most of the zip-files were about 50 MB in size, some larger because of a large file backed up. But some files were only 3 MB or even smaller with only 10 to 100 files in the ZIP.

On additional backups of this job most of the backup-files are very small and the job is creating a rather large number of backup-files for a small amount of data to be backed up. There were no files pruned until now, so the size of the files has not changed since creation.

Is the file-size-setting working incorrectly or did I miss something in the configuration?

I´m running AISBackup 2.6.0.314 on Windows XP SP2, the target-drive of the backup is a NTFS-drive with 800 GB free space.

Markus
Barry
Site Admin
Posts: 1529
Joined: Tue Aug 20, 2002 3:16 pm

Zip file sizes

Post by Barry »

AISBackup will try and ensure that the backup zip files reach the specified size, and this can be seen from backup session 1.For subsequent backup sessions the size of data is usually smaller and perceived premature split is probably owing to the different phases a backup job goes through: Using a zip file size of 25MB backup ‘zip’ files are split when:
  • The size of the zip plus any remaining pre-compressed file size is > 25MB

    The pre-compressed size of the file is > 25MB (This is where there is only one file per zip).

    There is a backup phase change, e.g. Normal files, Registry files, Opened exclusive files.

    There is a change of disk – this is because the disk drive letter is not held within a zip file.

    The number of files per zip is reached
AISBackup keeps backup zip files fairly small to make the pruning phase more efficient.

Barry
Markus
Posts: 28
Joined: Sat Oct 19, 2002 7:34 pm

Re: Zip file sizes

Post by Markus »

Barry wrote: There is a change of disk – this is because the disk drive letter is not held within a zip file.
this seems to be the reason for the small files I see in the backup-job.
But I don´t understand why the disk is changed so often.
For example in one session the following files were created in this order:

ZIP-file with 4 files from C:
ZIP-file with 4 files from D:
ZIP-file with 9 files from C:
ZIP-file with 17 files from D:
ZIP-file with 34 files from C:
ZIP-file with 1 file from D:

and so on. The ZIP-files are not even near to the configured 50 MB.

Markus
Barry
Site Admin
Posts: 1529
Joined: Tue Aug 20, 2002 3:16 pm

Drive change

Post by Barry »

I do see the reason and this has been corrected in the latest upload, please try build 321.

The list of files for backup are sorted into normal files / hard links and even if there are no hard links the sort did not use the drive as the primary sort key, i.e. sort on drive + hard link status. Even though no harm was done, other than too many zip files, this is now fixed.

Barry
Markus
Posts: 28
Joined: Sat Oct 19, 2002 7:34 pm

Post by Markus »

Hi Barry,
lokking good now, file-sizes are as expected.
Thanks for the quick fix.
Regards
Markus
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