Improving 7z extraction speed

[pgtaylor88]

Would it be possible to increase Bandizip's extraction speed for 7z files, especially those using LZMA compression?

To test, I made two 5GB 7z files in 7-Zip 24.08 using the default compression settings, except one was made using LZMA and one was made using LZMA2, and compared the extraction speed time using Bandizip and 7-Zip:

LZMA2 archive:

7-Zip 24.08:  00:03

Bandizip 7.36:  00:04

LZMA archive:

7-Zip:  01:50

Bandizip:  03:38

The extraction speed is similar with LZMA2 but with LZMA, Bandizip is noticeably slower.

Also, I've noticed while Bandizip and 7-Zip have roughly comparable extraction speeds when extracting smaller LMZA2 7z archives, Bandizip starts to become slower relative to 7-Zip as the archive size increases:

10GB archive:

7-Zip:  00:07

Bandizip:  00:08

18GB archive:

7-Zip:  00:14

Bandizip:  00:15

30GB archive:

7-Zip:  00:26

Bandizip:  00:30

60GB archive:

7-Zip:  00:54

Bandizip:  01:02

I know the differences in speed aren't too significant and most archives are never going to be that large, but the differences in speed do become more noticeable as archive sizes increase.

Thanks.

[seyo IM]

Hello, this is Bandisoft.

Measuring the processing speed of archiving software would be highly inaccurate without precise and strict variable control. Factors such as whether your SSD has caching enabled or whether any antivirus service installed on the system interferes, can have significant impacts. When we conducted our own tests, there was a notable difference in the time it took to decompress a 65GB 7Z file using Bandizip on the same computer, ranging from 2 minutes 28 seconds to 3 minutes 19 seconds.

The difference in processing speed for archives compressed using the LZMA algorithm occurs because the default dictionary size used by Bandizip is larger than the dictionary size used in the 7Z format.

Thank you for using Bandizip, and contact us again if you have any other questions or issues.

2024년 9월 4일 수요일 오전 8시 53분 36초 UTC+9에 pgtaylor88님이 작성:

[pgtaylor88]

Hello,

I have a follow up question if it's not too much trouble.  Could you explain a little more why the current defaults result in a different extraction speed with 7z archives compressed by the LZMA2 algorithm versus when a 7z archive is compressed by the LZMA algorithm?  I know that the default compression algorithm for 7z archives has been LZMA2 for a long time; however, I still sometimes have to download large, older 7z archives that were compressed by LZMA, and those can take a long time to extract compared to the current versions of 7-zip or WinRar.  Are there any settings that could be tweaked in a future version of Bandizip that could help speed up the extraction?

Thanks.         

[seyo IM]

We have fixed an issue where the speed of decompression using the LZMA algorithm is not as expected. Thank you very much for your issue report.

Download Bandizip Test Version: https://test.bandisoft.com/BANDIZIP-SETUP-BETA.EXE

2025년 6월 16일 월요일 오후 1시 17분 36초 UTC+9에 pgtaylor88님이 작성: