p2p IO is extremely CPU intensive on NFTS

[abujafar]

Binary package hint: transmission

I have a fully updated karmic beta.
Transmission has become a very cpu intense application even when seeding one torrent only (95% of a pentium4 2.4Ghz).
The Jaunty version of this application was less cpu intense.

[abujafar (abujafar)]

See attached screenshot

[Charles Kerr (charlesk)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Please answer these questions:

* Is this reproducible?
* If so, what specific steps should we take to recreate this bug?

This will help us to find and resolve the problem.

[abujafar (abujafar)]

Unfortunately, I don't have any specific procedure to provide in order to reproduce this bug.
It happens to me every time and for each torrent (both in downloading and in seeding only mode).

[Charles Kerr (charlesk)]

Hm, I can't reproduce this.

What filesystem are you using? Is it NTFS by any chance?

[abujafar (abujafar)]

as i matter of fact i usually download my files to an NTFS partition (mounted via ntfs-3g driver).
Does transmission have problem with that?

I will download next files in my ext4 root partition and let you know if the problem is still present.

[Charles Kerr (charlesk)]

It's not really Transmission's problem, but the NTFS implementation used by Ubuntu and other distros seems to have a very hard time dealing with p2p IO efficiently...

[Charles Kerr (charlesk)]

Could you report back on how it goes in ext4?

[abujafar (abujafar)]

OK, transmission works normally while downloading files to ext4 partition.

[Charles Kerr (charlesk)]

bumping to the linux-ntfs package for a second opinion.

[abujafar (abujafar)]

i suppose ntfs-3g is the correct one. linux-ntfs currently provide only userland utilities.

[John Dong (jdong)]

Correct, ntfs-3g is the right package. And unfortunately I think it's "normal behavior" for the random write patterns of P2P to be slow and CPU intensive with a userland filesystem like ntfs-3g :(