Hacker News new | ask | show | jobs
by wyattpeak 1570 days ago
Does anyone know why RAR is better compression-wise than the two more modern standards?

It doesn't seem like it's been updated in a long time, and I would have expected modern software from two of the best houses in the world to handily beat it. Is it that good, or is it a matter of priorities, or something else?
4 comments
lifthrasiir 1570 days ago
> Does anyone know why RAR is better compression-wise than the two more modern standards?

It simply uses a much slower algorithm (prediction by partial matching, PPM) in the highest setting. Those modern standards are designed to be fast enough and improve the status quo in that performance target. If they were only concerned about the compression ratio there are tons of other algorithms that would handily beat RAR already.

link
sumtechguy 1570 days ago
7zip also has a ton of settings where you can get it in the same ballpark of compression ratio. But LZMA2 usually consumes more memory to do better. It also takes a decent amount of time the more you fiddle those settings. The defaults on 7zip are fairly tame but 'good enough'. I found in my cases if you turn on solid archiving and duplicate file matching you are usually just as good as RAR or usually better. But costs speed.
link
noAnswer 1570 days ago
> It doesn't seem like it's been updated in a long time

It is actively maintained. https://www.rarlab.com/rarnew.htm A view years ago, with rar5, it got a modernised file-format.

link
xattt 1570 days ago
UHARC is more efficient than any of them, but no one uses it.
link
useFAR 1570 days ago
UHARC looks abandoned and does not support 64bit OS

My memory might be bad on this, but UHARC niche was media files, while rar was good tool for everything.

link
useFAR 1570 days ago
>>Does anyone know why RAR is better compression-wise than the two more modern standards?

Because RAR was original compression algorith(I suspect - collection of different algorithms that are applied for different cases) and those two others are based on ONE generic algorithm, which is dumb.

>>It doesn't seem like it's been updated in a long time

Because rar is perfect and what I need. I'm still using RAR files - not interested in 7z and have no idea what is the other standard mentioned. RAR has recovery record, that 7z lacks - when you have archives, that are decades old and moved from one HDD to another, where HDDs develop faults and you need to recover files - that suddently makes difference why rar is still better than 7z, when your files are corrupted in 7z - they are gone.

WINRAR License is least concern for me, because when WinRAR was created, there were different times, when there was an idea, that auhor(and maintainer) should have all the legal rights to his work(and that also includes compensation) - not some company, that is employing talents. Also idea, that your work should be free to everyone was wild idea, when software developers had to pay all the bills and eat as well. Also, closed propiertary sources were historically better for security.

RAR comes from times, when zip was dominating(and it was bad archive) - rar was better at compression than zip and it was quicker to compress and it was also supported on Linux. I have no idea what is 7z doing nowadays, but when it was developed first, it was improving zip, which nobody liked at that time. Also, 7z even nowadays havce some limitations, which requires workarounds, which is time consuming in archive creation. Anyway, none of those arguments for not using RAR seems good enough for me in especially on non open source Windows environment. The only reason for me to stop using RAR would be if Windows had access to RAR (open) source.

link
josephcsible 1570 days ago
> WINRAR License is least concern for me, because when WinRAR was created, there were different times, when there was an idea, that auhor(and maintainer) should have all the legal rights to his work(and that also includes compensation) - not some company, that is employing talents.

The rights to WinRAR are held by a company, not an individual.

> Also, closed propiertary sources were historically better for security.

This is not true and was never true.

> Also, 7z even nowadays havce some limitations, which requires workarounds, which is time consuming in archive creation.

Like what?

link