For a thread ripper build with pcie 5 ssd; does primocache give improvements?
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Just my 2 cents… After having fried 5 expensive 3990x CPUs, I’d say avoid Primocache and similar variants. The Achillies heel of the Threadripper/Zen architecture is its Infiniy-Fabric. This dual-torus loop which connects all of the chiplets to each other and the central I/O die requires serialization and deserialization of the data. About half of this computational overhead can be distributed amongst the chiplets, but the other half is all concentrated in the central I/O die – notably the memory controller. The Crux of the Biscuit is that the central I/O die uses the previous FAB process – so if the chiplets are 5nm, the central I/O die can be 7nm or 10nm. The larger traces means more heat all concentrated in the memory controller. Compounding this, are manufacturers like Asus which set defaults for the SOC voltage (which is also the RAM and central I/O die voltages) way too high in their DOCP or EXPO profiles. For the 3990x, AMD recommends no higher than 1.15V while Asus boosted theirs to 1.4V+. With high I/O demands – like using Primocache with large PostgreSQL restores, BZZZZT goes your memory controller. I’ve even found that the motherboards get damaged – and neither will ever POST again.
I’ve found that Primocache cripples the IOPS for seek intensive tasks. For that, I run raw on striped NVME SSDs. For other tasks, Primocache CAN improve performance and will decrease the writes to your SSDs increasing their lifespan. That said, in my opinion I’d just fry the SSDs instead of risking the chance of frying a much more expensive CPU. That and SSDs are easily replaceable. To use Primocache, you have to make sure that you’re running at JEDEC speeds and voltages. Forget overclocking. The Threadrippers reliably throttle to protect the CPU chiplets, but much less so the central I/O die. I have a number of VERY expensive coasters on my desk attesting to this…
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Not for your use case. I use it for RAM Write caching on two HDDs. There’s nothing inherently wrong with the program.
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