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### Incorrect Calculation of Ratio

Posted: **Sun Jul 05, 2015 3:00 pm**

by **BaramAvraham**

Software Being Used:

Fedora 21 Xfce

Transmission 2.84 (14307)

Problem Encountered:

The transmission client is not calculating the ratio properly. As I type this the client is downloading a file that is only 62% complete but the ratio is 1.6. Clearly that cannot be correct. Since I have not completely downloaded the file how can I have uploaded it 1x already.

### Re: Incorrect Calculation of Ratio

Posted: **Sun Jul 05, 2015 3:31 pm**

by **x190**

bytes uploaded/bytes downloaded = 1.6

thanks for sharing.

### Re: Incorrect Calculation of Ratio

Posted: **Tue Jul 21, 2015 9:29 pm**

by **BaramAvraham**

Then I am correct, the calculation of the ratio is incorrect.

The point of a torrent is to transmit (up or down) an entire file not a partial file ad infinitum. Is a torrent client sharing files or bits of a file?

A ratio is defined as: “the quantitative relation between two amounts showing the number of times one value contains or is contained within the other.”

Imagine the case of two torrent users and two different 10 Mb files. The first seeder downloads 2 Mb of a 10 Mb file then because no one seeds the remaining 8 Mb the seeder uploads that same 2 Mb 3 times. Meanwhile the second seeder downloads an entire 10 Mb file then proceeds to upload the entire 10 Mb file 3 times. Both seeders end up having a ratio of 3.

Which ratio is more meaningful….more relevant; the one that has measured the number of bits transferred or the ratio that shows how many times the entire file has been transferred?

IF the transmission software is using the bit method of calculating the ratio THEN it is possible (assuming the default cutoff of 2 for seeding) that the person could seed the first 62% of a file to the cutoff and shutdown seeding the remaining 38% when they finally download it. Which is exactly what has happened in my case. IF I wished to change this then I would —after fully downloading the file— manually raise the seeding cutoff and ask the tracker for more peers.

Again, I repeat… is Transmission a bit transfer client or a file transfer client? A ratio should meaningfully describe what it is comparing. Is it just bits or is it files?

### Re: Incorrect Calculation of Ratio

Posted: **Wed Jul 22, 2015 4:17 pm**

by **cfpp2p**

No, the calculation of the ratio is correct. It's just what ratio you want to see. I've modified my GUI so that I display two ratios.

label: up to down ratio

bytes uploaded/bytes downloaded

and

label: seed ratio

bytes uploaded/total bytes to downloaded

The two will become the same when the download is complete. You won't know exactly when you have uploaded specifically each and ever byte of a file. There's nothing to say that you won't upload the same byte multiple times but for whatever reason never upload some other byte of a file. Only as an initial seeder and in a "super seeder" mode, which transmission doesn't support, would you have that kind of control.