Thanks. So it goes into ram automatically, whatever fits. In my case it'll be 256 GB ram so it should all fit, but that leaves 106 GB for the OS and engine hash (full 6 men syzygy is 150GB) or is it shared with the hash? Just wondering what size hash I can set in that case.
Syzygy on RAM Drive
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Re: Syzygy on RAM Drive
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Re: Syzygy on RAM Drive
Knowing that you will doing deep analysis on an EPYC server , you will want to max out hash at 128GB and just let the OS figure out which TB to cache to memory. Hash using large pages will best serve by using multiples of 2048MB . You might want to test out different configurations. I have a NVMe PCI that reads nearly at 3500 MB/s, so I really dont worry about it. It is what it is. You might be better off using 192MB hash for deep analysis. You will be surprised how quickly 128 cores will fill up 128 GB of hash - it will be just a few minutes really.yorkman wrote: ↑Tue Apr 28, 2020 6:13 pmThanks. So it goes into ram automatically, whatever fits. In my case it'll be 256 GB ram so it should all fit, but that leaves 106 GB for the OS and engine hash (full 6 men syzygy is 150GB) or is it shared with the hash? Just wondering what size hash I can set in that case.
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Re: Syzygy on RAM Drive
Wow. Hard to believe I haven't been on here since April. Yes, this is what I've always been doing. I always set my hash to 131071 MB. And I too use NVMe PCI.
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Re: Syzygy on RAM Drive
I use a gumstick (m.2) PCIE4.0 SSD and those rascals run like the wind.
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