Hello,
my english isnt good, sorry for it

it is possible to add the feature where you cann affect the max. upload and download speed for one torrent?

-------
bug ???
-------
I'm using KTorrent: 2.1rc1 on my gentooBox, Azureus was used befor. So I added some incompleted files from azureus to kTorrent, and the check of existing files is very very slow ? One file was about 40GB it takes over one hour to check it ??? how can I accelerate it ?



thx
masa

That feature is planned for 2.2.

As for the data check, with huge files, how much faster is AZ actually ?

Azureus and KT check at nearly identical rates on single-core machines (actually KT is a bit faster with Java5 and GCC precompiled Java Azureus, Azureus is a bit faster with Java6)

but Azureus appears to multithread checking of chunks on multi-core systems, making it markedly faster on those provided that disk IO can keep up.

But checking a 40GB file computes SHA1 hashes for 40GB of data, which is quite a CPU-intensive operation and going to take time, no matter what torrent client you use.

The fact that AZ manages to do it faster on a multiprocessor system, would indicate that the hash check is the bottleneck, if the disk I/O was the bottleneck, you can have 10000 CPU's it's not gonna go any faster.

On a single-core system of respectable speed, hashing does indeed appear to be the bottleneck, not disk IO. It starts to even out on my Core duo laptop with 2 CPU's and simultaneous hash checking.

Hmmm.... Actually, AZ is extremely faster than KT on my machine as far as I can remember. I'll test with some large torrents and I'll let you know the results.

If the hash check is the bottleneck we can probably speed it up by having a disk reading thread read into a queue which is emptied by the hashing thread, that way the hashing thread can allways be busy, and the disk thread can load chunks when they are needed.

When the disk thread would be reading from disk, the hash thread can keep using the CPU.

Another option maybe is to use mmap.

Did some tests with a 4.63 GB torrent, and AZ pulls it off in 4 minutes 10 seconds, KT does it in in 5 minutes 56 seconds. So there is room for improvement.

I'm running an amd64 3500+, so a single core, single processor system.

George wrote:Did some tests with a 4.63 GB torrent, and AZ pulls it off in 4 minutes 10 seconds, KT does it in in 5 minutes 56 seconds. So there is room for improvement.

I'm running an amd64 3500+, so a single core, single processor system.

That is more than 40% faster
It would be good advertising if ktorrent could beat that.

Hmm, well, do you think it's a hashing algorithm, or Sun's billion-patent specializing JIT compiler managing to generate better machine code for such a repetitive procedure?

jdong wrote:Hmm, well, do you think it's a hashing algorithm, or Sun's billion-patent specializing JIT compiler managing to generate better machine code for such a repetitive procedure?

We can get it better, just a matter of using your brains and finding some time to do it.

thumbs up for the max up & down for each torrent

keep up the good work