SSD Level-2 Cache Size Topic is solved

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SSD Level-2 Cache Size

Post by Gamer2592 »

Hello everyone.

Just wondering if there is a guideline (RATIO) to select a SSD size for Level-2 caching vs the HDD size it will be caching ?

On my computer, I use a 240GB SSD to cache a 2TB HDD. Is my SDD too small? too big ? Or the correct size ?

I did not find this information in the documentation.

Thank you in advance for your responses.

PS. Being using PrimoCache for over 1 year and it works great.
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Re: SSD Level-2 Cache Size

Post by Jaga »

This is really subjective for most people. I have a personal preference though: no less than 10% data coverage, and ideal would be 20% or higher. So if your HDD has 1TB of data you want to cache on it, your 240GB L2 (over-provisioned so it only has a 200-220 GB volume for the L2, right?) would be right around 20%.

When you go too far under 20%, your hitrate starts to suffer due to blocks being swapped in/out too much. Just my opinion on it, others may have their own. 10% would be my absolute minimum coverage rate, or the L2 SSD is really going to suffer write/re-write wear.
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