this post was submitted on 01 Nov 2023
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Serious question: why would one use .7z when .tar.gz and .tar.xz exist?
Why would you use any of them when zip exists?
For an average user they offer no advantage.
Zip has a worse compression ratio than 7z, and that's a disadvantage for the average user (for example, a user with an email attachment size limit that they need to stay under).
If Windows natively supports one of the better alternatives, there's no reason to keep using zip. It's a 30 year old format, and it's something that regular users will happily just go with whatever's default.
Not only does Zip have a worse compression ratio than 7z, but it even takes longer to make the zip due to the fact the windows zip program is single threaded.
I know for a fact .tar.xz offers the best compression rate for my use case.
Then you aren't an average user.
It also takes forever to pack.
I ran benchmarks for syslog compression/decompression, and ended up using plzip, which used lzma, just because it was the fastest decompression while still having only marginally worse ratio.
But it still takes forever to pack.
Yeah definitely sounds just as simple /s
For me .zip on Windows is equivalent to .tar.gz on Linux - used when I just want to send a folder in a single file very quickly.
Also handy when sending an archive to a weaker machine, that might take a while to unpack a 7z compressed at the highest setting.
.7z is when I want to send a folder encrypted, or heavily compress something to archive (like a database, documents folder, or disk image/iso). It seemingly does the impossible, shaving the size from say 60GB down to 40GB compressed if you use solid mode (which has downsides if there are multiple files in the archive). It's incredibly flexible, but the defaults are pretty solid for most cases
7z files pack and unpack more quickly than Zip files since the windows zip program is only single threaded.
It's like when .zip was popular I guess?
Tar.gz is a two step thingy too (maybe under the hood 7z is too) so the extraction process always seems long?
Pro tip: Tar knows what to do if you try to untar a tar.gz file. It Just Works(tm).
So do zip files lol
Yes but can winzip do tape backups.
What do you use tape backups for?
Nirvana bootlegs.
Yeah I know, and it's only useful rarely as if you can extract directly to the target, you don't need to have an intermediate copy (or do intermediate copying). Really nitpicking ofc.
Eh? 'tar xvf foo.tar.gz' is technically 2 steps I guess, but that's pretty well hidden from the user.
.7z and .xz are (essentially) the same compression algorithm but it's applied either to the whole chunk of data, or to individual files. That has its pros and cons.
More practically though windows users don't know what the hell tarballs are, and I've even seen some bonkers handling like turning a tar.gz into a tar first that you then have to unpack.
7z files can be browsed without decompressing the contents, and tar.xyz archives preserve file system attributes like ownership. They have totally different use cases.
If I want to back up a directory on my drive, I would use tar.xz. But if I want to send some documents to other people, I would use 7z.
They're Windows users
Tared files are cancer and should never be used for any reason.
Clearly you've never used Linux
Clearly you never needed that single file quickly from a 5gb and 12,000 files tgz archive.
Wtf are you on... It's literally just a way to turn a bunch of files into one. You can feed it into a makefile and make a single file installer like nothing. Apps are based on the concept. It's a key technology for all sorts of applications
It's so simple it works for anything, anywhere... It's like saying virtualization is cancer. It's often annoying when you have to interact with it directly, but everything we love is built on it
Tared compressed files are bad archives. You can't retrieve a single file without unpacking everything. You can't add new files or replace contents of existing files without unpacking and repacking everything. They are just very outdated and have poor design. There are no reasons to use them.
They're bad for storing files, but a great way to turn a folder into a file.
Installers don't need to be modified or used in part
Why do you continue talking about installers? That's not the reason people invented archives and compression.
Ok, you have this design, which every installer in the world uses. Some are more compressed, some are signed, some bootstrap a downloader - but at the end of the day, every downloadable installer uses the same basic concept. From Windows installers to dmg to flatpacks to app bundles - same basic idea.
A tarball is a bunch of files laid end to end, it's good for one thing and one thing only - treating a bunch of files as one. It's great at that... If you want to compress it, it's not context aware enough to let you decrepit them individually - they're encrypted as one file
It's a bad way to store compressed archived info, I'll grant you that, but it's a great way to share a program or library to reproduce a bunch of files that make no sense to handle individually.
For another example, what about the layers of a photo editing program? What about the individual tracks in a music editing program?
It's an incredibly useful pattern that is used in countless ways. It's simple, easy to implement, and used everywhere to great effect
Again, not the reason for archives.
... Do you think archives are just when you store old files on magnetic tape?
For fucks sake... That's what YOU think! And that's the problem! TAR is a shit archive format. Deal with it.