arc

I have been searching for some time and cannot find any official documentation on how to calculate the memory consumption for the L2ARC headers. I did find one person claiming that each header consumed 70 bytes and that each ZFS record required a header. C

I have a solid state hybrid drive with a 32 GB NAND cache... I set the ARC to 1 GB before knowing what it was at all, but can I just turn it off altogether since I already have that?

Edit: I realized I knew too little about ZFS when I wrote this. Sorry guys. Hello, I don't have a ECC memory so I don't want ZFS to use memory as ARC. I have a 256 GB M.2 PCIE SSD and 1 TB of HDD. And I will buy a 32 GB Optane module. And I have a SATA SSD 256 GB. How much for ZIL needed for...