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mickeyoneil

Max 8 cpu cores - Have 16

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I have a xeon processor with 8 cores with hyperthreading. When I run dmesag|grep smp it states I have 16 cores which exceeds the NR_CPUS limit of 8. I can't seem to find anywhere on how to increase this max so I can utilize all 16 cores. Is this possible and how? Huge deal breaker if I cant utilize all 16 cores. Thank you.

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I have a mobo with Dual X5650's and trying to get this to work first of all, I'm happy to disable hyperthreading however that still leaves me with the dilemma of 8/12 cores working, and 24 possible logical threads, this computer is for a) 10G networking bridge b) SSD Caching c) PLEX Transcoding Host, so yes, the extra horses are needed and 2 would be very useful.

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it's' kernel config parameter,

CONFIG_X86_MINIMUM_CPU_FAMILY=8 

 

Juns bootloader he creates a custom zImage which loads up the DSM software, could he, compile a new kernel with the LIMIT set to something like 24/32 something in the region of 2017... server cores. Seeing as we can get a single CPU with 8 cores then HT to 16 logical, 8 is becoming rather limiting.

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it's' kernel config parameter,

CONFIG_X86_MINIMUM_CPU_FAMILY=8 

 

Juns bootloader he creates a custom zImage which loads up the DSM software, could he, compile a new kernel with the LIMIT set to something like 24/32 something in the region of 2017... server cores. Seeing as we can get a single CPU with 8 cores then HT to 16 logical, 8 is becoming rather limiting.

 

Actually, the bootloader only creates a custom zImage (bzImage) for AMD boards. Otherwise the zImage is the stock 8451 zImage from 3615xs.

 

Compiling our own kernel is an option, though it is cleaner if we use the official one (since it gets replaced at update any way).

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i'm going to have similar dilemma when I switch to baremetal on my Supermicro X10SDV board. It has 8 core, 16 threads.

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Juns bootloader he creates a custom zImage which loads up the DSM software, could he, compile a new kernel with the LIMIT set to something like 24/32 something in the region of 2017... server cores. Seeing as we can get a single CPU with 8 cores then HT to 16 logical, 8 is becoming rather limiting.

 

If you look here viewtopic.php?f=2&t=20216

 

You can found a git link to scripts used by Jun to create your own bootimage, i'm in the " how it works" and there are some tricks to do to obtain a regular boot image.

If you have needed knweldge, you can try by yourself.

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i'm going to have similar dilemma when I switch to baremetal on my Supermicro X10SDV board. It has 8 core, 16 threads.

Disable hyper threading.

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