I believe you are right about the dump that I receive in RAR format is not packed using the most extreme settings RAR has to offer.
But still, I expect 7-zip to be at least 30% to 50% more efficient than anything winRAR can bring to the table. Regarding my dumpfiles that is.

At the cost of time.

I tried packing 2 GB of Access databases. 7z (Ultra) was about 26% smaller, but needed 20 minutes, while RAR (best) needed 6 minutes.

26% more effective, but 3x slower.

I'm not sure if "smallest archive size" is the only way to find the "best archiving utility". I think RAR's compression time/size ratio is quite OK. I also like its ability to detected CRC errors in (split) archives, report missing archives, repair defective files using recovery records, keep broken files, extract from split archives even without the full set,... and so on.


Just guessing, but perhaps your 200 GB file is packed with "super fast" because it would need longer to compress / decompress a strong compressed file (7z "ultra" or RAR "best"), than downloading the extra 11 GB (because of weak compression).

Quote from: Shades on August 12, 2010, 10:52 PM

I believe you are right about the dump that I receive in RAR format is not packed using the most extreme settings RAR has to offer.
But still, I expect 7-zip to be at least 30% to 50% more efficient than anything winRAR can bring to the table. Regarding my dumpfiles that is.

At the cost of time.

I tried packing 2 GB of Access databases. 7z (Ultra) was about 26% smaller, but needed 20 minutes, while RAR (best) needed 6 minutes.

26% more effective, but 3x slower.

I'm not sure if "smallest archive size" is the only way to find the "best archiving utility". I think RAR's compression time/size ratio is quite OK. I also like its ability to detected CRC errors in (split) archives, report missing archives, repair defective files using recovery records, keep broken files, extract from split archives even without the full set,... and so on.


Just guessing, but perhaps your 200 GB file is packed with "super fast" because it would need longer to compress / decompress a strong compressed file (7z "ultra" or RAR "best"), than downloading the extra 11 GB (because of weak compression).

Your point is very true...with a high capacity connection.

However, I have to pull those files through a 512KBit connection which is costing about 120 USD/month. You can get cheaper, higher rated connections over here, but those lines here are really 'overbooked' and unreliable.  In my situation I simply lose too much time downloading. Besides that, my download is immediately ready to be stored on the least amount of DVD's.

Shades: sending only a diff of the dumps isn't an option?

(creating different archives per file or folder, and deleting the source files after compression are invaluable features)

Thanks for reminding me of the only two features I miss from WinRAR.

However, a bit of investigation led me to an AHK script/utility called 7-Zip Each File. It's a lot easier than trying to figure out how to do it by command-line. The only thing it seems to be missing is the option to delete the source file after compressing.

Quote from: Shades on August 14, 2010, 03:06 AM

Your point is very true...with a high capacity connection.

However, I have to pull those files through a 512KBit connection which is costing about 120 USD/month. You can get cheaper, higher rated connections over here, but those lines here are really 'overbooked' and unreliable.  In my situation I simply lose too much time downloading. Besides that, my download is immediately ready to be stored on the least amount of DVD's.

I find your way of measuring efficiency odd...
1. It takes you longer to produce the smallest size zip but requires less download time.
or
2. It takes you longer to download a moderate size zip but saves you some compression time.

Either way, you are simply swithcing the "wait" between the 2 processes.

If the zip is prepared by someone else, then he/she always produces a bigger zip to save his/her time, that is a matter of his/her choice and should not be taken as a factor in determining WinRar's efficiency.

Granted, you have a point there...if you are using a system (or work-flow) where the bottleneck is almost the same size than the rest of the system.

However you do not seem to grok that the bottleneck in my complete work-flow is the internet connection...let me clarify with an example. Imagine a bucket of water, an empty bucket similar to the first one and a straw to get the water from one bucket to the other.

I use a VPN connection to let a quad core PC create the archive in 2 to 2,5 hours the download will take an x amount of time. Downloading the moderately compressed archive easily takes x + 6 to 8 hours more (if I am lucky, internet here in Paraguay is really not as stable, as in the northern hemisphere of the globe...even with business subscriptions).

Over here I use an i7 PC that takes 30 to 40 minutes to unpack the highly compressed archive and I am already way into the importing process when the moderately compressed would be in. As I am paid by the hour, my benefactor does not complain at all.

Besides that, with all the computing power that is available in modern PC's, do you really think it should be wasted by playing the latest games or editing/encoding your home video alone?

WinRAR for me because of:
- the best speed/size ratio,
- nice command line support,
- file names encryption (SQX had that but died).

I don't have (much) experience with either of these, but 7-Zip also has command-line support (not sure how good it is) and file name encryption.

Now I feel ashamed because for password protection I could swear the opposite. When was it added? Has "error recovery" feature been added too? Either way speed issue remains.

It seems I am too much behind

However you do not seem to grok that the bottleneck in my complete work-flow is the internet connection...

I understand internet connection speed is the bottleneck and I also understand in your case, the best archiver will be the one which compresses the most.

However, no archive utility relies on internet connection to do its job, so a measure which is based on internet connection speed can not be used to judge how good an archive program is.

I have almost never given much thought to compression - use what comes with the OS (ususally providing a combo of bz2, gz and zip), or little old peazip. On the servers I still tend to stick with gz - files are bigger, but the time and CPU load compressing large log files with the other formats is too disruptive

Although watching people with different priorities in the time vs cpu use vs size debate trying to argue the best product out (nicely) is rather entertaining

Quote from: tslim on August 26, 2010, 01:19 PM

a measure which is based on internet connection speed can not be used to judge how good an achieve[sic] program is.

This is false. You seem to believe that there is a single best program for everyone, that they can be judged in absolute terms.

No! My statement is not FALSE. It has nothing to do with "single best program for everyone"
I just want to point out that, if there is a formula which measure the power of archive program, then "internet connection speed" can never be a factor of that formula.

In a layman concept, you can of course relate anything as a mean to measure the usefulness of archive program, but any conclusion you made will become subjective and (no offense, please) is a crap. Just like I could say, because my keyboard is crack and therefore very difficult for me to type/input into MS Excel, I therefore find MS Excel is not good.
Would you agree with me that "keyboard" is a solid factor to measure how good MS Excel is?

Damn, I missed the PA Free. Although I had tested the latest "Full" version a few weeks ago and wasn't too impressed ...

7-Zip 9.16 Beta: http://majorgeeks.com/7-Zip_d4603.html

7-Zip 9.17 Beta: http://downloads.pcauthority.com.au/article/2418-7-zip-917-32-bit

Anyone have a Coolrar english version? Would like to try it out.