[SOLVED] Using CPU to it's full potential during Zip File Decompression 7Zip

[akaikisaki]

Hello All,

While creating/ splitting Zip files using 7Zip, I get the option to choose the number of threads which can be used to Compress the file more quickly.

However, while decompressing, the cores and threads are not being utilized to their full potential. Task manager shows just 5 to 10% CPU utilization.

So, is there a way to utilize all the Cores/ Threads and make Decompression faster?

Thanks.

 

[kanewolf]

Hello All,

While creating/ splitting Zip files using 7Zip, I get the option to choose the number of threads which can be used to Compress the file more quickly.

However, while decompressing, the cores and threads are not being utilized to their full potential. Task manager shows just 5 to 10% CPU utilization.

So, is there a way to utilize all the Cores/ Threads and make Decompression faster?

Thanks.

Uncompressing may be limited to the speed of your storage subsystem.
Also 7zip only supports some formats with multithreaded decompression -- https://sourceforge.net/p/sevenzip/discussion/45797/thread/136f029b/

 

[akaikisaki]

Uncompressing may be limited to the speed of your storage subsystem.

If by that, you mean the Hard disk and the SSD, I have tried in both, and the results were the same.

Also 7zip only supports some formats with multithreaded decompression -- https://sourceforge.net/p/sevenzip/discussion/45797/thread/136f029b/

Thank you for providing the link.
It was stated by one user that Bzip2 would utilize all cores, but it's not.
I have tried every setting, by changing the Compression Level and Archive Format Combination, but still no change.

 

[akaikisaki]

Also, is there any other Zip archive software that fully utilises all the cores and threads?

 

[TerryLaze]

Also, is there any other Zip archive software that fully utilises all the cores and threads?

You can use the command line version of 7zip.
-mmt= is the amount of threads you want it to use
test.zip is the output
c:\portables\ is the input,you can use a single file here but 7zip uses one thread per file so you need to use a lot of files at once to get usage on all cores.

7z.exe a -mmt=32 test.zip c:\portables\


Compression works by finding stretches of the same thing and shortening them,for example if there are 10 zeros in a row you can substitute that with 10x0 which would be a 60% compression ratio,was 10 long before is now 4 long.
The more separate parts you cut a single file into the fewer stretches of the same thing you are going to find so multithreading on a single file is rather pointless.

 

[akaikisaki]

mmt=32

7z.exe a -mmt=32 test.zip c:\portables\

Thank you for helping me out. This will be the first time that I'll be using the Command line for archives. Had to search the internet for a beginner's guide.

The one you mentioned, is the command for Adding to Archive, right.

Can you help me with the command for extracting file. I'm not able to get the correct command. I tried this:

CD C:\Program Files\7-zip
C:\Program Files\7-Zip>7z e -mmt=16, after this I don't know how to add the rest of the command..

The input file directory is:

E:\Test.7z

Output = C:\Users\blabla\Desktop

 

[TerryLaze]

7z.exe e -mmt=16 E:\Test.7z -oC:\Users\blabla\Desktop

Your C drive is protected by windows so it might not work unless you run the command line as administrator.

 

[akaikisaki]

7z.exe e -mmt=16 E:\Test.7z -oC:\Users\blabla\Desktop

Your C drive is protected by windows so it might not work unless you run the command line as administrator.

Thank you for the command lines. It worked.
However, the CPU utilization was the same, and no change.

Guess it has something to do with the Hard Disk or the SSD, better SSD = better decompression, I guess.

 

[TerryLaze]

Thank you for the command lines. It worked.
However, the CPU utilization was the same, and no change.

Guess it has something to do with the Hard Disk or the SSD, better SSD = better decompression, I guess.

As I tried to explain before,it's all about the number of files.
If you only have a small number of files you can only use a few cores.