[Question] : tie a task to a cluster when it shares memory resources

[Daniel Lezcano <daniel.lezcano@linaro.org>]

Hi all,

I am not expert on the NUMA area and the scheduler but I was wondering 
the following:

On numa a process can define a memory policy to optimize access because 
remote memory access is suboptimal.

On a multicluster (aka multipackage), eg. Bi-Xeon 4 cores, the scheduler 
load balancing can spawn/balance a task to the second cluster even if 
the task is resulting from a fork or a pthread_create. If I am correct 
that could impact the performances due to L2 cache misses, no ?

Won't it be more efficient to tie a task to a cluster when it shares 
memory resources with another task on the same cluster ? and when the 
task does 'exec', this constraint is removed.

Thanks
-- Daniel

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