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

From: Daniel Lezcano
Date: Tue Oct 29 2013 - 13:32:39 EST



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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