Re: Threadding issue

[Petr Janda <elekktretterr@xxxxxxxxxxxxxx>]

1) I can bzip the whole ktrace dump and put it on my webserver, will 
that help you?
2) How do i switch to libthread_xu?

Petr

YONETANI Tomokazu wrote:
> On Thu, Jul 27, 2006 at 02:42:29PM +1000, Petr Janda wrote:
>   
> > http://leaf.dragonflybsd.org/mailarchive/users/2006-07/msg00184.html
> >
> > Can someone please fix it? Its really bugging me, and Im not the only 
> > one to have that issue. Some people say growisofs does the same.
> >     
>
> IIUC, libc_r's thread scheduler may call sys_set_tls_area() at most twice
> per call, so if the application tries to switch between threads very
> frequently, it can call sys_set_tls_area() very often.  There are many
> places in libc_r's code where the thread scheduler is called, but the
> easiest way to make it happen is calling sched_yield().
> For example, src/engine.c in gxine has the following code:
>
> 		static gboolean js_queue_cb (GtkWidget *widget, GdkEventClient *event,
> 																gpointer data)
> 		{
> 			exec_t *js;
> 			while ((js = g_async_queue_try_pop (js_queue)))
> 			{
> 				/* spin; play_exec gets this & the GDK lock in reverse order */
> 				while (pthread_mutex_trylock (&widgets_update_lock))
> 					sched_yield ();
> 				pthread_mutex_unlock (&widgets_update_lock); /* JS 'play()' needs it */
> 				engine_exec_obj (js->cmd, js->obj, js->cb, js->cb_data, js->ecb, js->src);
> 				free (js->cmd);
> 				free (js->src);
> 				free (js);
> 			}
> 			return TRUE;
> 		}
>
> I wonder what happens if you use libthread_xu instead of libc_r
> (not sure if it's easy to replace the use of pthead library).
>
>
>