Page 1 of 1

L1 Cache greater than 32 GB

Posted: Wed Feb 19, 2020 1:29 pm
by rwohleber
Greetings all,

We have PrimoCache running on a Lab SAN here in our Data Center that we are experimenting with to replace FreeNas in our production SANs. As we all know, FreeNas utilizes all available RAM to be an L1 Read Cache, and then there are ways to utilize SSD's or NvME drives as L2 Cache and also Write Cache. It's performance is legendary, however we are switching to an all-HyperV architecture.

We do NOT, however, want to use Storage Spaces for a few reasons that are internal and not relevant to this topic. Without Storage Spaces we cannot use Tiering.

We were wondering if the 32GB limit of L1 cache can be removed/bypassed? Our SAN has 256 GB of RAM and it doesn't make sense to NOT utilize that for READ cache. Cache obviously can make-or-break the performance of a SAN, and due to the large size of our SAN (approximately 120 TB) we use Disks as opposed to all SSD. We're not budgeted to migrate to Enterprise SSD's until 2023, the CFO is making us get our large investment out of this SAN array.

So... 32 GB limit. What can be done about this on the Server product?


Re: L1 Cache greater than 32 GB

Posted: Fri Feb 21, 2020 7:39 pm
by Jaga ... php?t=4143

The L1 size limitation is actually 1.5 TB. The 32 GB size in the dropdown list is merely there for convenience - you can enter in whatever value you need to use, and it will reserve that from available RAM.

I just tested on a L1 cache task I normally keep set to 28 GB by changing it to 33 GB, and it worked as expected.

Re: L1 Cache greater than 32 GB

Posted: Sat Feb 22, 2020 4:17 am
by support
Sorry for the late response. The L1 size is up to 2TB now and L2 is up to 2044GB. Please see ... ation.html
As Jaga said, users are able to manually type the cache size in the input box.

Re: L1 Cache greater than 32 GB

Posted: Sat Feb 22, 2020 6:01 am
by Jaga
Good to know L1 got a raise, adding to notes. Cheers.