Re: Solaris10/Sparc, tor and threads

[Roger Dingledine <arma@xxxxxxx>]

On Thu, Aug 20, 2009 at 12:52:38PM +0200, Thomas.Hluchnik@xxxxxxxxxxxxx wrote:
> my fist steps with running tor on Sparc are successful. I did it with
>Solaris10, Sun-CC on a E450 with 4 CPU.

Great.

> When doing configure I found
>a message:
> 
> configure:2435: You are running Solaris; Sometimes threading makes
> cpu workers lock up here, so I will disable threads.
> 
> This is a pity cause I have 4 CPU.

Well, Tor still can use your other CPUs -- it falls back from threading
to forking. Be sure to set "numcpus 4" if you want to use all of them.

(Alas, Tor only uses cpuworkers for decrypting create cells -- it doesn't
use them for AES or for TLS. So it doesn't balance load over multiple
CPUs nearly as well as it could. That's on the low-priority todo list.
Patches appreciated. ;)

> Has anyone experience with tor on
>Sparc-Solaris here and can explain why this is?

Long ago, we got reports of Tors crashing when trying to use threads.
That was many years ago now though, so it could be that it works better
now. Does Solaris support pthreads correctly, or does it prefer its own
native version that we'd need to teach Tor about?

> What would happen if I
>enforce threading?

You could try it and find out. :)

I think you'd need to edit configure.in and modify this part:
if test x$enable_threads = x; then
   case $host in
    *-*-solaris* )

--Roger