Search speed in AMD

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Krzysztof Grzelak
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Search speed in AMD

Post by Krzysztof Grzelak » Wed Mar 25, 2020 5:33 pm

I have such a request and question. I write immediately that I am not a programmer. I have a processor AMD Ryzen Threadripper 1950X. I am looking for information on how to increase the search of 1 core in the processor AMD Ryzen Threadripper 1950X. Please, if possible, a code in C ++. Thank you in advance for any information.

mar
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Re: Search speed in AMD

Post by mar » Thu Mar 26, 2020 2:39 pm

My experience with AMD so far is that AMD loves everything cached in registers.
Any memory access (assuming in L1) is much slower than on Intel, or perhaps it's the other way around and AMD is much faster when executing reg-reg opcodes)
Optimizing compilers do this for you, obviously, so I don't see how this would help.
I've also heard that BMI2 is emulated on AMD, thus much slower than on Intel (I don't use BMI2 in my program).
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Michael Sherwin
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Re: Search speed in AMD

Post by Michael Sherwin » Fri Mar 27, 2020 12:54 am

mar wrote:
Thu Mar 26, 2020 2:39 pm
My experience with AMD so far is that AMD loves everything cached in registers.
Any memory access (assuming in L1) is much slower than on Intel, or perhaps it's the other way around and AMD is much faster when executing reg-reg opcodes)
Optimizing compilers do this for you, obviously, so I don't see how this would help.
I've also heard that BMI2 is emulated on AMD, thus much slower than on Intel (I don't use BMI2 in my program).
I can verify that BMI2 runs at only 2/3 of the node rate of the popcount version on my AMD 3950x.
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Dann Corbit
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Re: Search speed in AMD

Post by Dann Corbit » Fri Mar 27, 2020 4:13 am

ipman chess shows that the AMD BMI mode stinks, stanks, stunks.
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