Javier, 

Thanks for the explanation. One more question. With the
simics images of cloudsuite, did you bind the threads to specific core?


On 07/03/2013 0:53, Javier Picorel wrote: 

> Dear Mahmood, 
> User
threads interact with the OS through functions of the c-standard library
(e.g., glibc, uclibc). These functions among other things, trap to the
portion of code of the 
> OS that executes system calls. In the past,
OSs were only able to interrupt a process/thread in user mode. Nowadays,
most kernels are preemptive. This means that 
> when your user thread
traps to the OS, it can be rescheduled. If the OS sees that the running
queue of a processor is empty, it will try to steal a process/thread
from another 
> processor. Therefore, it might be the case that the
system call (and the user thread) gets rescheduled and executed on
another core. However, I would say that generally 
> user-threads trap
and execute system calls on the same core (kernel preempted or not). 
>

> Let me know if this answers your question. 
> Regards, 
> Javier
> 
>
-------------------------
> 
> FROM: Mahmood Naderan
[[email protected]]
> SENT: 02 July 2013 11:13
> TO:
[email protected]
> SUBJECT: similarities among threads
> 
>
Dear all, 
> 
> Is there any study or observation regarding the
similarities among threads in cloudsuite workloads? For example, assume
core10 hits a syscall. Is he going to execute the OS code himself or it
will pass to another one (say core0). 
> -- 
> 
> Regards, 
>
Mahmood

-- 

Regards, 
Mahmood
 

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