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Is it possible to disable CPU (Intel) cores in BIOS, and if yes what HP/DELL (others?) 1U/2U servers would allow this?

It is becoming difficult to find new server hardware with dual core CPUs, most of new servers are Quad Core ones, and so the cost of Oracle licenses makes server upgrades unreasonably complicated. Which brings me to the question above.

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not really an answer (don't have chance to test it), but I found this: en.kioskea.net/faq/… - would it work? –  nhek Dec 8 '09 at 17:49
Thanks. Yes I know about maxcpus. However there is a fear that oracle might see all the cores through some hardware probes, and legality of this method (in regards to the licensing agreement) is unclear. Disabling cores in BIOS should be a cleaner approach. –  monomyth Dec 8 '09 at 18:02
Are you sure that disabling a core in BIOS would affect Oracle licensing? Oracle generally doesn't allow you to license a subset of the cores in the system if you are merely using software partitioning to restrict which cores Oracle can access-- they require an approved hardware partitioning solution. I doubt that BIOS settings would qualify. Various licensing restrictions also talk about the number of cores that could be installed in the box if you're using various Standard Edition/ Standard Edition One products. –  Justin Cave Dec 8 '09 at 20:57
Justin, good point. I have no idea if this is permitted, but logically I see no reason why it shouldn't be, because it precisely addresses the software partitioning problem. Disabled cores are not available to the operating system and/or software at any level. –  monomyth Dec 8 '09 at 22:07
I agree that it seems logical, but I have learned that legal issues don't necessarily flow logically from a technology standpoint. I'd make sure that either your legal department or your Oracle Sales rep buys off on disabling cores in the BIOS before making any decisions. –  Justin Cave Dec 8 '09 at 22:14
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up vote 14 down vote accepted

With the HP ProLiant G5 and newer (G6, G7, Gen8) servers (e.g. DL380, ML370, etc. - Anything after the Intel 5400-series CPU's), it is possible to disable half of the cores available to the server.

This is a BIOS switch labeled "Processor Core Disable" with options "All Processors Enabled" and "Disable One-Half of cores per Physical Processor."

This is a standard and recognized means of reducing core count for tricky licensing scenarios.

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thank you, exactly what I was looking for! –  monomyth Dec 9 '09 at 17:44
IBM UEFI-based Intel 5500 and above servers also allow you to run only one/two/four/etc. cores per CPU. –  MikeyB Dec 10 '11 at 14:00
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You could consider running VMWare ESXi on the hardware, and only present 4 processing cores to the guest. The "overhead" should be negotiable as there would be four free cores.

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I could, but I won't. With a bios setting you can easily revert it whenever licensing will change, giving oracle all 100% of hardware power. ESXi will still be using memory and cpu. Virtualization is not a magic pill, no matter how much we want it to be. It has its uses, but this is not one of them. –  monomyth Dec 8 '09 at 18:16
I would recommend you carefully review the merits of VMWare for exactly this scenario and not simply brush it aside as ineffective or inefficient. –  SirStan Dec 8 '09 at 18:25
Agree with SirStan. This is the exact sort of place where virtualization shines: you need a specific hardware platform that is becoming hard to obtain. A VM will give you that flexibility, and if your license changes, then you can just add more cores to the VM, or even move the virtualized machine to new hardware and add more resources there. –  Satanicpuppy Dec 8 '09 at 18:56
No. by running the Oracle machine in a VM, you gain very granular control of CPU resources independent of the options offered by a particular machines BIOS. Three people can't see a better option. They're not all completely senseless. It also gives you hardware independence which is an advantage not to be ignored. I run compute servers in VMs. It costs me ~5% performance, which is a price I'll pay for convenience and in my case trivial SAN boot. I'm not aware of a BIOS that lets you do anything other than disable all cores but one in a socket. That I suspect isn't good enough. –  xenny Dec 8 '09 at 20:59
I know this is an old thread, but in case anyone else finds it, Oracle does not recognize the validity of only assinging the Virtual Machine running Oracle x number of CPUs out of a total of y cpu cores in the server. They require a license for all the cores on the server if it is running VMWare. If you are running it this way make sure you get in writing, from Oracle, that this is a supported configuration and you only need a licence for x number of cores, not a license for all the cores on the server. –  user144159 Nov 5 '12 at 19:29
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