Messages in this thread | | | Date | Thu, 21 May 2015 02:08:09 +0530 | From | Afzal Mohammed <> | Subject | Re: [PATCH 4/4] nohz: Set isolcpus when nohz_full is set |
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Hi,
On Sun, May 17, 2015 at 07:30:50AM +0200, Mike Galbraith wrote:
> Yeah, tying nohz_full set to isolcpus set up an initial condition that > you have to tear down with cpusets if you want those cpus returned to > the general purpose pool. I had considered the kernel setting initial > state to be an optimization, but have reconsidered.
> Given that kernel initiated association to isolcpus, a user turning > NO_HZ_FULL_ALL on had better not have much generic load to manage. If
On a quad-core desktop system with NO_HZ_FULL_ALL, hackbench took 3x time as compared to w/o this patch, except boot cpu every one else jobless. Though NO_HZ_FULL_ALL (afaik) is not meant for generic load, it was working fine, but not after this - it is now like a single core system.
Regards Afzal
> he/she does not have CPUSETS enabled, or should Rik's patch rendering > isolcpus immutable be merged, he/she would quickly discover that the > generic box has been transformed into an utterly inflexible specialist > incapable of performing mundane tasks ever again.
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