Recent changes to feature-requests

Support for larger LZMA2 dictionary sizes

Michael Lackner — Sat, 25 Jun 2022 12:00:16 -0000

Recent versions of 7-Zip now support even larger dictionaries in the LZMA2 context for data deduplication and higher efficiency when compressing very large amounts of data on a system with large amounts of memory (tens to hundreds of gigabytes, or even terabytes).

While p7zip (just like xz) is still limited at 1536 MiB dictionaries, 7-Zip now supports up to 3840 MiB, resulting in roughly 40 GiB of memory use for single-threaded operation and slightly over 500 GiB for 24 compression threads. This seems useful, as machines evolve to have more and more RAM that can be used for deduplication hash tables.

It's specifically effective for compressing e.g. lots of virtual machine disk images for long-term offline storage, or generally large data sets featuring high block-level redundancy.

I would like to request similar (if not even larger) dictionaries to be implemented in p7zip to make use of the resources of large servers and workstations for more efficient compression.

Thank you!

#42 Please support symbolic links inside zipfiles !

Jeff Han — Sun, 14 Jun 2020 02:09:45 -0000

I fixed tar link file decompress as regular file.
OR you can download https://github.com/szcnick/p7zip the dev branch.

#42 Please support symbolic links inside zipfiles !

Jeff Han — Thu, 11 Jun 2020 15:38:14 -0000

I tested that tarfile cannot be decompressed correctly, but zipfile can be decompressed correctly.
Am i right？

#42 Please support symbolic links inside zipfiles !

Igor Pavlov — Mon, 25 May 2020 07:47:31 -0000

Maybe I'll look later. Not now.
Thanks!

#42 Please support symbolic links inside zipfiles !

Sam Tansy — Sun, 24 May 2020 22:22:36 -0000

@ipavlov: Do you still want such file/s? I saw in 7z-19.00 that it recognizes symlinks, which doesn no signify support. Anyway, if you did I attach a simple sample, there is a zip and tar inside, along with file list within archive.

#47 tar + rar support

Sam Tansy — Tue, 12 May 2020 02:56:07 -0000

E_NOTIMPL means it's not implemented. You can't create rar archive with any tool other than rar. That's their (rarlabs) policy and license.
You can unpack, no problem, but create only with their tool/s. You have to read the license.

Don't know whta's with your tar-ball. Show me you command line.

PS. Would you mind to not attach original message if you don't relate to it? That will keep it tidy and not scare with volume to read. And when you do, just quote relevant fragment, not the whole message. I can read and can see what I wrote before.

#47 tar + rar support

Sam Tansy — Fri, 08 May 2020 20:29:08 -0000

Rar support is on all teh time, so to speak. You need to have Rar.so in your p7zip Codecs directory (where 7z.so is, usually /usr/lib/p7zip or /usr/local/lib/p7zip).

$ find /usr/lib/p7zip
/usr/lib/p7zip/7z
/usr/lib/p7zip/7z.so
(...)
/usr/lib/p7zip/Codecs
/usr/lib/p7zip/Codecs/Rar.so

I don't know how to extract .tar.gz/bz2/lz/xz, in one step - it's more of a question to 7zip discussion/help.

And last, what dit you mean by .tlz? Tar.lzma or tar.lz? If .tar.lzma then see above, 7z can decompress lzma alone files, it .tar.lz then you'll need to patch your p7zip yourself. Check 7zip section on lzip savannah.

tar + rar support

Thomas Bodlien — Wed, 29 Apr 2020 17:38:26 -0000

Can you add tar (tgz,tbz2,tlz,txz) and rar support?

#46 Support extraction from ZIP files if "total number of disks” value "zip64 end of central dir locator" equals 0

Johan van der Knijff — Thu, 19 Mar 2020 15:01:06 -0000

Fantastic, thanks for that!

#46 Support extraction from ZIP files if "total number of disks” value "zip64 end of central dir locator" equals 0

Igor Pavlov — Thu, 19 Mar 2020 10:48:05 -0000

Thanks!

I'll change 7-Zip code.
And 7-Zip will ignore that minor error. So 7-Zip will open such archives faster than 20.00 alpha.

Recent changes to feature-requests

Support for larger LZMA2 dictionary sizes

#42 Please support symbolic links inside zipfiles !

#42 Please support symbolic links inside zipfiles !

#42 Please support symbolic links inside zipfiles !

#42 Please support symbolic links inside zipfiles !

#47 tar + rar support

#47 tar + rar support

tar + rar support

#46 Support extraction from ZIP files if "total number of disks” value "zip64 end of central dir locator" equals 0

#46 Support extraction from ZIP files if "total number of disks” value "zip64 end of central dir locator" equals 0

#42 Please support symbolic links inside zipfiles !

#42 Please support symbolic links inside zipfiles !

#42 Please support symbolic links inside zipfiles !

#42 Please support symbolic links inside zipfiles !