Note that there’s a difference between kb/s (kilobits/second) and kB/s (kilobytes/second). To be precise, kb/s = kB/s divided by 8. In this tutorial we use kB/s (like most torrent clients do). This means that you might need to calculate your max speed in kB/s yourself if the speedtest only gives you the results in kb\s (so divide by 8 then).

Settings 1-4 can be found in the options, settings or preference tab of most torrent clients.

1. Maximum upload speed

Probably one of the most important setting there is. Your connection is (sort of) like a pipeline, if you use you maximum upload speed there’s not enough space left for the files you are downloading. So you have to cap your upload speed.

Use the following formula to determine your optimal upload speed…

for relatively fast connections (upload >20 kB/s)

upload speed * 85%

so if your maximum upload speed is 40 kB/s, the optimal upload rate is

40 * 85% = 34

Slower connections (upload <20 kB/s) need a little more space so I use this formula

upload speed * 75%

so if your maximum upload speed is 12 kB/s, the optimal upload rate is

12 * 75% = 9

2. Maximum download speed

Although setting your maximum download speed to unlimited may sound interesting, in reality it will only hurt your connection.

Use the following formula to determine your optimal download speed…

for relatively fast connections (download >60 kB/s)

download speed * 95%

so if your maximum download speed is 200 kB/s, the optimal download rate is

200 * 95% = 190

And again I experienced that Slower connections (upload <60 kB/s) need a little more space so I use this formula

(download speed * 85%

so if your maximum upload speed is 40 kB/s, the optimal upload rate is

40 * 85% = 34

3. Maximum connected peers per torrent

Yet another setting that you don’t want to max out. I experimented quite a lot with the max connected peers settings and came to the conclusion that both high and low number hurt the download speed of a torrent. The following setting worked best for me.

upload speed * 1.3

so if your maximum upload speed is 40 kB/s, the optimal amount of connected peers per torrent is

40 * 1.3 = 52

I didn’t noticed a difference for fast or slow connections here.

4. Maximum upload slots

1 + (upload speed / 6)

so if your maximum upload speed is 30 kB/s, the optimal number of upload slots is

1 + (30 / 6) = 6

5. Maximum half-open tcp connections

This tweak was mentioned in previous post and I noticed some debate about the optimal settings. So I played around with this tweak on different machines and came to the conclusion that the best setting is

for relatively fast connections (download >60 kB/s)

upload speed * 2 (I will advise to never go higher than 1000)

And for Slower connections (download <60 kB/s) can have a little extra.

upload speed * 4

These numbers are not as holy as the other tips, but they are a good guideline. For more info on the max half-open tcp tweak read our previous post.

6. Optimize your internet connection

The TCP optimizer is a freeware utility that optimizes your internet connection. I found it very useful and it helped speeding up my connection for regular internet activity and for downloading torrents. Just download it, and move the slidebar to your maximum download rate (note that it’s in kb/s). Don’t try to set it higher because that will hurt your download speeds!

I hope these tips are useful and help you to get the most out of BitTorrent. Note that these these tips are the result of extensive “trial and erroring” but still very subjective. For the uTorrent users out there, 1c3d0g wrote a great tutorial, the numbers might slightly differ from the ones I found though.

Source: Speed up your torrents II