Compression App SUPPORTING MultiThreading

nForcer

WinZIP
WinRAR
WinACE
WinTAR

NONE of which support a feature sought after by few but is equally as important when the task presents itself - multithreading compression capability.
I finally discovered one such application that DOES support this feature, tested myself, and its name is 7-zip @ www.7-zip.org.

How it compares to compression prorams like those listed above, I'm not able to say at the moment but utilizing multithreading on my Dual 2.4GHz Intel Xeon w/HT, while compressing a 4.7gig DVDR-ISO to ZIP format, (in Normal mode) took less than 40 minutes - where WinRAR was taking several hours to do the same!!!
Like I said before, I did not do any file-size vs time lapse comparissons yet but the simple fact I can compress an entire DVD in 30 minutes is intriguing enough for me to switch back to ZIP from my long favorite 'RAR' format.

So for those of you who may be in the same situation as myself, might I suggest you give this little app a try and see for yourself how much time you could be saving, and CPU cycles you could be utilizing!

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Well I structured that like I was going actually going to post it in the NEWS section but I figure, get the word out, surely someone will benifit from it - and if there is significant interest, I'll do a short article on it compared to programs like WinZIP/WinRAR/etc.

Matth

The benchmark mode, for my system, was about 30% higher with multithread enabled (Intel P4 640 hyperthreading). Multithreading is only available for compression, and may not be available for all compression types - in my version, it's greyed out for everything other than the native 7Z format.

7Z's own format has good compression, within spitting distance of RAR, or maybe better, but 7Z format, especially at higher levels, is quite slow to compress.

If you are seeing the option for all formats, I guess it's time I updated - It would also be interesting to see the benchmark results for dual core and dual CPU compared to hyperthreading.

nForcer

Thus far I can vouche that its compression method using ZIP formatting is MUCH MUCH MUCH faster than any other application and even under the most extreme options. I'm eagerly looking forward to my completition of my dual core 820 and see how well it performs.

Matth

From a post in alt.comp.freeware
http://www.kikizas.net/en/apps.7z.html

A comparative test of 7-ZIP versus RAR, interesting reading...

In only ONE group of files (the word docs) could RAR beat 7Z compression, though the speed of 7Z at maximum was painful. 7Z at normal + solid, was only a little slower than RAR's best, with compression beating RAR except on that last data set.

Strange that there was practically no gain from "SOLID" on the word docs, when you would expect a reasonable degree of repeated elements between them.


It's also possible that a custom setting of 7Z may allow a better balance of speed and compression on a particular file set, or maybe the "Maximum" option would be a better balance than Ultra ... the gain from normal to ultra, against the massive increase in time, is clearly at the point of diminishing returns.


Another way of assessing compression, is on the basis of communication efficiency.
1. Time to compress
2. Time to transfer at a certain speed (used to be dialup, but using a 512k broadband as another base may be more current)
3. Time to expand

Where multiple downloads are expected, then it moves toward favouring best compression at almost any cost, so long as the time does not become a problem.