I’m considering building a home NAS. I plan to make an all-flash NAS for three reasons:
- Spinning rust can’t keep up with the IOPS demand (~2000 iops) of the cryptocurrency full nodes I’ll run on it with the number of disks I’d be using (2-4).
- I don’t need huge capacity (10TB ideal size)
- I hate, hate, HATE waiting for HDDs to spin up after being idle. I did it for 6 years…I’m done waiting.
My question is one I don’t have the hardware to test for myself at the moment: How does ZFS handle putting drives in lower power states when they aren’t being used? Let’s assume that I sequester the cryptocurrency usage to one non-ZFS ssd, and that the majority of the NAS’s time will be spent idle, with brief periods of activity. One of the main advantages of SSDs is that they can go to sleep and wake up in milliseconds. Does ZFS leverage this, or would the drives stay at full ‘idle’ power, instead of going to sleep while not in use?
When I had a hardware RAID card I could configure the spin-down time. Actually, even in Windows I can still do that. I don’t see that option with SSDs, and my google-fu isn’t turning up anything of use. I know if the pool is constantly being read from (99% of the crypto node activity is random reads) it won’t put the disks to sleep because they’re always in use. Hence why I was planning to put the blockchain data on its own device.