Selective compression

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Brian2
Posts: 21
Joined: Fri Aug 25, 2017 5:41 am

Selective compression

Post by Brian2 »

Is it possible, in the same job, to configure which file types are compressed and which not?

I would like to compress all file types except video, audio, picture and archive.
No compression for avi, mp4, jpg, mp3, zip, etc
Barry
Site Admin
Posts: 1538
Joined: Tue Aug 20, 2002 3:16 pm

Re: Selective compression

Post by Barry »

AISBackup already maintains a list of files that should not be compressed, but for some reason did not contain .JPG. The list is maintained in Tools / Do not Compress File List. AISBackup maintains a list of compression stats so can be updated automatically by selecting the Auto Update button, however I found a very large number of files were added with extensions that are used in Microsoft’s system files with extensions like ‘.A90647CFE67532AF’.
Brian2
Posts: 21
Joined: Fri Aug 25, 2017 5:41 am

Re: Selective compression

Post by Brian2 »

I'm trying to speed up backups a bit because when compressing it's over 4x slower that no compression.

Long ago, in the XP era I think there was compesssion program called PKZIP (IIRC).
It had compression levels ranging from 0-9
Anything above level 5 was very slow with marginally better compression.
I wonder if it's possible AISBackup also could have multiple compression settings? I think even one extra "medium" would be quite tradeoff between speed and size.
Barry
Site Admin
Posts: 1538
Joined: Tue Aug 20, 2002 3:16 pm

Re: Selective compression

Post by Barry »

Compression level in zip files is set between 0 and 9, where 0 is no compression and 9 is maximum compression. Tests were run using the different compression levels and it was found that using the level 2 gave the best speed vs. compression ratio, albeit 20+ years ago. I am compiling some statistics on run times for backing up my Windows 11 ‘C’ drive and will report back when this is done.

The long run times are mitigated when the same backup is run again, as only changed and new files are added to the backup, the deleted files are marked as deleted so that they do not appear in the later backup sessions. As you know, each backup session looks and behaves like a full backup.

Barry
Barry
Site Admin
Posts: 1538
Joined: Tue Aug 20, 2002 3:16 pm

Re: Selective compression

Post by Barry »

I re-checked the AISBackup code, AISBackup already uses the quickest zip method, it is still slower than using the uncompressed option, but mitigated when the backup job is used again to make a new session as only new and changed files are actually backed up.

AISBackup’s performance can be improved by adding AISBackup.exe to the anti-virus software’s exclusions section (the process section). In Windows Security this is done by using the Virus & threat protection / Virus & threat protection settings Manage settings / Exclusions / Add an exclusion / choose process / Enter AISBackup.exe / Click Add.

Some statistics using a backup of Window 11 ‘C’ drive, 1,084,729 files using 354GB:

AISBackup without being excluded in antivirus software:
Compressed 4 hours 4 minutes
Un-compressed 2 hours 29 minutes.

AISBackup added to antivirus software exclusions:
Compressed 2 hours 46 minutes
Un-compressed 1 hour 31 minutes.

Barry
Brian2
Posts: 21
Joined: Fri Aug 25, 2017 5:41 am

Re: Selective compression

Post by Brian2 »

Thanks for the replies Barry!

I didn't know about the do not compress list.
Now I've best of both worlds (speed and compression)
I got quite a bit on video stuff like workshops and tutorials. They come in many formats. Likely I didn't spot every extention yet but most of my video files are .mp4.
Adding that to the list gave a huge speed boost.
Below my list you may concider adding to a next release.

7z
AVCHD
WebM
flb
gz
jp2
jpeg
jpg
m4a
m4b
mkv
mov
mp4
png
rar
vob
wma
wmv
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