S2D Cache Ratio 1:1 Query

[Steve21]

Morning All,

 

Just looking at speccing up a full school refresh for servers, and wanted to check if anyone knew about the priority of caching for S2D

 

For example if I went for an unusual 1:1 ratio with SSD/HDD on a 2 way mirror, would it effectively become a full flash array while both hosts are up because the redundancy part of the data would always fall back into the HDD as it's not used, while the main servers would always be cached due to the large cache? (Same logic on a 1:2 ratio on a 3 way mirror etc?)

 

Or could you still end up with primary data in HDD while redundancy sits in flash?

 

Thanks,

Steve

[TRS-80]

Why not just go all flash? How much data do you have?

[Steve21]

Why not just go all flash? How much data do you have?

 

"Currently" about 22TB, although most of that is junk as seems my new place hasn't cleaned up in a decade! But either way size aside, going full flash for redundancy only doesn't seem very cost effective if a 1:1/1:2 does work, thus the question

 

Steve