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  • 1.  Multi Core vs Multi Processor

    Posted Aug 16, 2010 03:45 PM

    Will a single processor with four cores perform the same as a dual processors with two cores each?

    The reason I ask...

    I'm looking at getting two HP DL300 series servers for my virtual environment. I will be running less than 10 virtual machines total and will probably load balance among the two. I have a total of 40 users. I have 1 SQL Server with two databases. I have one terminal server that mostly gets used for office applications.

    My current environment has a single Dell Poweredge 2900 with a dual core dual processor setup. It's running 7 virtual machines including two sql servers and it's not being taxed very hard as it is. Processor usage is generally low with occasional spikes, but no performance loss has been noticed and according to some of the free virtual performance calculators it's being heavily underused and could stand to have 16 more virtual machines.



  • 2.  RE: Multi Core vs Multi Processor

    Posted Aug 16, 2010 03:46 PM

    Will a single processor with four cores perform the same as a dual processors with two cores each?

    Yes, and in some case Quad core is better performance, even when the cores are slower.



  • 3.  RE: Multi Core vs Multi Processor

    Posted Aug 16, 2010 03:47 PM

    I know that two six core processors will have more performance than a single six core. What I'm curious about is would, for example, two three core processors have more performance than a single six core processor at the same megahertz and equal cache?



  • 4.  RE: Multi Core vs Multi Processor

    Posted Aug 16, 2010 03:54 PM

    two three core processors have more performance than a single six core processor at the same megahertz and equal cache?

    That's not what you said. You said dual core vs quad. You can't buy a 3 core processor, so that's a moot point. Quads are better than Dual core. Six Core is a completely different story, they are better than quad, but it's completely different technology, not the same comparison.



  • 5.  RE: Multi Core vs Multi Processor

    Posted Aug 16, 2010 04:07 PM

    First of all thank you for your response.

    Sorry for the confusion. For some reason I got to thinking I hadn't actually pointed out what I was trying to say. It was just for illustration purposes anyway.

    Basically I was just trying to find out if performance of multiple cores spread out over two processors was better than the same amount of cores in a single processor. Which I believe you all have answered for me.



  • 6.  RE: Multi Core vs Multi Processor

    Posted Aug 16, 2010 04:13 PM


  • 7.  RE: Multi Core vs Multi Processor

    Posted Aug 16, 2010 04:17 PM

    Basically I was just trying to find out if performance of multiple cores spread out over two processors was better than the same amount of cores in a single processor. Which I believe you all have answered for me.

    glad to help. And yes, multiple cores over 2 sockets is the same (or less depending) as all cores in 1 socket. Six cores is wrapped up into 1 socket, and splitting them up into 2 sockets (which is 3 core per socket) is really the same thing.

    Dual Core is somewhat older technology, and Intel did some improvements to cache and core size (and power) which equates to a much better "core" processor than Dual Core, which is why 4 cores in a single socket is almost always better than 2 socket of Dual Core, simply by the way the Dual Core was designed, it was Intel's first iteration. Six core has made a complete overhaul of the core line, and makes the quads look pathetic by comparison, but in this example you are splitting the same cores across socket, not using different technology.

    for your purpose, yes the cores are the same. 4 sockets 2, 2 socket with 4 or 1 socket with 1. If you could do it, that would be identical performance IF we are talking faking the cores in the socket to only use 2 core (this can be done on some quad cores so there are no logical cores, in the BIOS). It's not the same as Dual Core (early versions of core) processors versus Quad Core. You change many characteristics of the technology not JUST the core speed / or number of cores per socket. That's what I was attempting to explain. Dividing cores among sockets has neglible difference, than compacting them into 1 socket. There is a vast difference between a true Dual Core processor vs a True Quad or True Hex core however.

    Dual Core (even faster core speed) isn't as fast as a lesser speed quad core, in a single socket. (at least in my experience)



  • 8.  RE: Multi Core vs Multi Processor

    Posted Aug 16, 2010 03:55 PM

    I say stick with more cores over more sockets, plus it will save you on licensing costs, and probably perform just as good if not better, in my opinion as well.