Questions about block size

[Shoonay]

I don't get it, so my drive is 4K or not? The cluster size is 4K. And, it is advised to choose the block size same as the cluster size or less, but only higher values are available... ?
(128kb was the default value when I created this cache task)

[janusz521]

Your logical sector size is 512 bytes so it is compatible with PrimoCache 4.0.1. And with some simplification blocks and clusters create groups of sectors used by the file system.
Probably you should consider creating a smaller L2 cache than about 477 GB. Such a big cache with small block size consumes a lot of RAM.

[Shoonay]

Not a problem with 64GB's, I'm just confused about the block size I should be using to get the best performance in games.

[Jaga]

I don't get it, so my drive is 4K or not? The cluster size is 4K. And, it is advised to choose the block size same as the cluster size or less, but only higher values are available... ?
(128kb was the default value when I created this cache task)

This article does a fairly good job of explaining what a 4Kn (4K Native) drive is, and why the industry is transitioning away from 512-byte sector based drives.

Your drive clearly indicates it has an underlying 512-byte hardware sector size.

Primocache requires a "block size" equal to or greater than the volume's logically declared sector size, which was defined when the volume was created. i.e. if your logical volume was created with a 4KB formatted-sector size, the Primocache block size has to be 4KB or larger (a multiple of 4KB to be precise).

You should still be able to select and use the 4KB block size in Primocache, so it's odd that only 8KB is showing up as the smallest unit. You may want to check the Drive Manager section of Windows management to see that the logical volume was created with 4KB clusters, and not 8KB.

Not a problem with 64GB's, I'm just confused about the block size I should be using to get the best performance in games.

Usually *not* the smallest block size available, since it creates a much larger overhead in terms of RAM use, and in my /personal/ experience tends to put too large a requirement on system resources to manage. I like to go with a block size of either double, or quadruple volume cluster size. So if you formatted the logical volume with 4KB clusters, use either 8KB or 16KB block size. I run apps and games daily, and am using a 16KB block size.

[Shoonay]

You may want to check the Drive Manager section of Windows management to see that the logical volume was created with 4KB clusters, and not 8KB.

Where? Here?

[Support]

@Shoonay, your drive is not a 4Kn drive. The cache block size has nothing to do with this 4Kn issue. The reason why you don't see the 4KB cache block size is that the target drive is too huge and 4KB block size does not work for it. You might need a big block size to reduce the cache memory overhead.

[Shoonay]

Okay, that's not a problem, thank you for all the explanations, I've changed the cache to 16KB and it works just fine with only 3.18GB of overhead.

[Support]

3GB overhead still seems a lot and it's a waste. I would suggest 64KB.

[ryh]

"3GB overhead still seems a lot and it's a waste. I would suggest 64KB"

Do u mean is a waste in term of performance?

Because if someone got 64GB RAM (or even 32GB) and do not utilise even half of that then no difference if overhead is 1GB or 3GB.
But if size of overhead affect overall performance (like is taking lot of CPU usage by PrimoCache) then - how significant difference is overhead performance impact for example between 1GB overhead and 3GB?

[Shoonay]

Exactly my question.
If it's the leftover RAM that is your concern I don't care personally, with all the caching for 3 of my disks still got 30GB's free on desktop with the daily programs loaded.
That being said, when switching from 128KB to 16KB block size I do see a *slight* boost, like a few seconds, in last save loading time of Cyberpunk 2077 at launch.