Zandr Milewski
Dabbler
- Joined
- Oct 5, 2013
- Messages
- 13
I recently built a home backup/media server using Seagate 8TB SMR drives, and have been pondering how to tweak FreeNAS to make the most of these drives, given their unique write characteristics. I'll describe what I've done so far, but everything is still in testing, so if nuking the drives and rebuilding the system is in order, that's fine.
The box has 6 8TB drives in a RAIDZ2, 16GiB of RAM (maxed out), and a pair of 120GB mSATA SSDs. It's booting FreeNAS 9.3.1 from a 16GB USB drive.
Workload is backup/archive and media server. Clients are almost exclusively Macs. Once it sees "production", it will be on a connected UPS.
I've already moved the system dataset to the SSDs (configured as a mirror). I'm not sure if there's any point in booting from the SSDs; seems like the boot volume should be pretty much read-only.
I've turned off atime on the SMR volume.
It seems like I should get swap off of the SMR drives, and on to the SSDs. If I understand correctly, the write cache is limited to a fraction of real memory, not memory+swap, so using lots of the SSD for swap won't help any.
Is there a good way to measure what portion of my workload is sync, to determine whether putting an SLOG on SSD would be worthwhile? (or have I misunderstood that thread?)
Thanks,
-Zandr
The box has 6 8TB drives in a RAIDZ2, 16GiB of RAM (maxed out), and a pair of 120GB mSATA SSDs. It's booting FreeNAS 9.3.1 from a 16GB USB drive.
Workload is backup/archive and media server. Clients are almost exclusively Macs. Once it sees "production", it will be on a connected UPS.
I've already moved the system dataset to the SSDs (configured as a mirror). I'm not sure if there's any point in booting from the SSDs; seems like the boot volume should be pretty much read-only.
I've turned off atime on the SMR volume.
It seems like I should get swap off of the SMR drives, and on to the SSDs. If I understand correctly, the write cache is limited to a fraction of real memory, not memory+swap, so using lots of the SSD for swap won't help any.
Is there a good way to measure what portion of my workload is sync, to determine whether putting an SLOG on SSD would be worthwhile? (or have I misunderstood that thread?)
Thanks,
-Zandr