Re: Can we add or remove CPUS dynamically on BL870 BLADE (180 Views)
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Occasional Visitor
nnrao1502
Posts: 2
Registered: ‎01-07-2014
Message 1 of 3 (213 Views)

Can we add or remove CPUS dynamically on BL870 BLADE

Hello expert Admins,

 

Is  there  any  option to   add/remove  CPUs at OS  level  on BL870 Blade.  I see  an  option at EFI shell.

 

cpuconfig [cpu #] [on/off] ............ We are  looking  for  an option at OS itself  without  rebooing  the  server.

 

Thanks

nnrao

 

 

Honored Contributor
Duncan Edmonstone
Posts: 5,684
Registered: ‎08-05-2000
Message 2 of 3 (183 Views)

Re: Can we add or remove CPUS dynamically on BL870 BLADE

I don't think there is an exact equivalent to the cpuconfig tool available at EFI, but you can use the psrset command to assign CPU cores to a seperate PSET. If you then don't actually schedule any processes to run in that new PSET, the CPU is pretty much "off". There are probably some low level differences in how this works compared to cpuconfig especially for cores on a single socket and how they use cache, but I would imagine the upshot is broadly the same.

 

See man page for psrset for more details.

 

On Superdome and the older partitionable servers that support iCAP you could also use the icapmodify command to acheive this, but not on BL870.


HTH

Duncan
Honored Contributor
Duncan Edmonstone
Posts: 5,684
Registered: ‎08-05-2000
Message 3 of 3 (180 Views)

Re: Can we add or remove CPUS dynamically on BL870 BLADE

I would also ask why you want to do this - if for licensing purposes, you have to be careful as it may not be recognised as a mechanism to restrict licensing by the ISV (e.g. Oracle don't recognise using PSETs on their own as a mechanism for managing per-core licensing, but they _do_ recognise it when PSETs are used in conjunction with Secure Resource Partitions - SRPs)


HTH

Duncan
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