RPM vs Cache/Memory?

[rfc1925]

I bought 2 DS720+ where one will replicated by an offsite snapshot sync.

This will be a backup system with mostly write, except in a DR situation. Total data is about 2.5 TB

I mistakenly bought 5400rpm drives & wonder if a cache drive or memory upgrade would negate the need to swap to 7200rpm?

 

[EAZ1964]

here is my 10 cents:
Typically, 5400RPM drives will saturate ethernet speed 110MB/s easily. Only if you have a lot of IO small files/database applications, where access time becomes a bottleneck, you will see a noticeable difference.

I hope that you did avoid SMR disks by the way.

 

[rfc1925]

they are Seagate IronWolf ST6000VN001 & Im considering swapping to Seagate Exos 7E8 ST6000NM0115

 

[johndnz]

the 5400rpm ironwolfs are pretty good for a 5400rpm drive - I get 180-190mb/s raw off the 4tb model and about 210mb/s off the 8tb (wheras the WD 5400rpm drives are slowwww). The same size exos is only slightly faster at 226mb/s sustained

with just 2 1gbe ports even the 5400rpm ironwolfs will pretty much saturate both ports.

Also the exos run hotter and are markedly noisier (have rack mount servers at work with piles of them in).

 

[rfc1925]

the 5400rpm ironwolfs are pretty good for a 5400rpm drive - I get 180-190mb/s raw off the 4tb model and about 210mb/s off the 8tb (wheras the WD 5400rpm drives are slowwww). The same size exos is only slightly faster at 226mb/s sustained

with just 2 1gbe ports even the 5400rpm ironwolfs will pretty much saturate both ports.

Also the exos run hotter and are markedly noisier (have rack mount servers at work with piles of them in).

Not sure I need to plug in the other eth jack, as only 1 server is talking to it. This site uses only SAS so noise isn't a concern but heat could be.