Please help me get a zip file as small as possible.

airborne

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Every week or so I backup 2.5GB of user data to a USB flash drive.
I use 7zip with encryption and I can't get the zipped 2.5gb file smaller than around 2.3GB, half the original file size would be acceptable or else what the point.

How can I get it smaller, as small as possible?
Its mixed files mostly program database type files, form Onenote, Emclient etc
 
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What type of files are they?
7zip is pretty good so Im guessing the files are already compressed.
 
The best you'll get is .tar.gz but then again unix is as scarce among the young folk as Mozart...

I.e. gzipped tarball ...
 
backup to flash drive.....we'll there's your problem. sync to storage, then back that up...or use floppies
 
What type of files are they?
7zip is pretty good so Im guessing the files are already compressed.
The majority are uncompressed, txt etc.
Buy a bigger flash drive...

This.
Not sure why you're hassling over an extra few mb of compression.

backup to flash drive.....we'll there's your problem. sync to storage, then back that up...or use floppies
I need a small portable backup medium which a flash drive suits perfectly and a 32gb gets filled up pretty quickly.

I'd like to know better methods to make smaller zip files in general. Are there any 7zip settings that I'm perhaps missing or should know about?
 
It all depends on the file type really, if possible try converting to a text or csv format.

You can also maybe try zipping multiple times, try one archive program, archive, unarchive, archive. Then archive that archive using 7zip.

Using 7zip: Specify 'qs' in Parameters field, boils down to trial and error basically ;)
 
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2.5 GB is a huge amount of txt data. Are you sure there is not some photos or pictures in there?

That would be much more understandable since most images are already compressed and do not benefit much by being put through a compression tool.
 
The majority are uncompressed, txt etc.





I need a small portable backup medium which a flash drive suits perfectly and a 32gb gets filled up pretty quickly.

I'd like to know better methods to make smaller zip files in general. Are there any 7zip settings that I'm perhaps missing or should know about?

If you can make it csv format then you can compress like 80%.
 
The majority are uncompressed, txt etc.





I need a small portable backup medium which a flash drive suits perfectly and a 32gb gets filled up pretty quickly.

I'd like to know better methods to make smaller zip files in general. Are there any 7zip settings that I'm perhaps missing or should know about?
No, it is what it is, as the type of files you back up does not seem to compress well. You might be able to get a few more megabytes with settings.

Buy a bigger drive.
 
As most have said you're unlikely to get much better. It's all about entropy. The more of that in the data the less you'll be able to compress it. Good compression would in all aspects look like completely random data so it can't compress any more. If you can see a lot of repeated data then the compression isn't very good.

If 7zip can't compress it further you've likely reached the limit but you can try winrar with the continuous archive option.
 
You can try the different 7zip options such as bzip2 etc (and on maximum compression); but if you're only getting down to 2.3Gb from 2.5Gb then the majority of the data isn't plain text, its probably already (internally) compressed.
 
Every week 2.5 gb of data?
CAD drawings?I think you need to go through the backups and see what is taking up the space and is incremental backup not an option?
 
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