An idea for research

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RobF99
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An idea for research

Post by RobF99 »

I have idea for Romex to research and to possibly incorporate into PrimoCache. It might break some kind of new ground in caching.

I do some independent scientific research and one of the areas that fascinates me is conservation of symmetry. This could be implemented in a way into PrimoCache.

Assuming a 32 Gb system. Take away 4 Gb for program memory needs it leaves 28 Gb for caching. If you split that up evenly and give PrimoCache L1 14 Gb and leave the rest for Windows which would generally have around 14 Gb for caching this leaves a situation that might not be optimal for PrimoCache cache hits. I know Windows uses a complex eviction policy but assuming it uses LRU and LFU and PrimoCache uses a similar policy, it is likely that older data evicted by Windows would also have likely been evicted from PrimoCache. In other words, there is no real general benefit to using exactly the same approximate eviction policy as Windows.

However, if Windows uses LFU and LRU and PrimoCache has an option for the opposite eviction policy, i.e. MRU, MFU, logic and this principle of symmetry says that most of the time, what Windows evicted will still be in L1 and vice versa.

Of course logic says this but it might play out differently under general use. Anyway, it is an idea for you to research and see if that idea works and implement it as an option in PrimoCache. In this case of 50/50 cache between Windows and L1, it is pointless approximately copying the Windows policy but implementing the opposite policy makes better and correct use of the memory dedicated to cache.

You could call it asymmetric caching or something to that effect.
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Support
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Re: An idea for research

Post by Support »

:D creative idea! In fact, we are looking into how to better integrate with Windows file caching, and one of the key points is to avoid duplicate caching. Thank you for your idea!
RobF99
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Re: An idea for research

Post by RobF99 »

You are welcome. I am glad you see merit in the idea. :-)
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