Re: thread ids, task ids and subsystems

[Peter De Schrijver]

On Wed, Apr 02, 2003 at 08:51:21PM +0200, Marcus Brinkmann wrote:
> On Wed, Apr 02, 2003 at 08:27:35PM +0200, Volkmar Uhlig wrote:
> > You still have to delete and re-create tasks to implement fork/execve
> > for example. And there performance matters in particular if your one and
> > only privileged thread may need 100us or more to perform the thread
> > creation/deletion and is blocked for that time... 
> 
> Yeah, right.  Thanks for all the input.
> 
> > Additionally, you have significant cache-line migration costs to get the
> > request onto the other CPU. When deleting and re-creating the task, it
> > will show up on the wrong CPU and the load balancer has to migrate it
> > afterwards adding another X-CPU scheduling request (per thread!). So
> > better do it on the right CPU in the first place.
> 
> Ouch :)  That makes sense.
> 

But this does not apply to P4 hyperthread instances, does it ?

Thanks,

p2.