Hi:
I want a rysnc server that I can run backup my synology nas with hyper backup at weekly base as second cold storage backup. (Most of time the server will be offline) The hardware I use is i3-12100, Asus h610i, 32G DDR4-3200. 5x WD gold 2tb. LSI 9211-8i 6G SAS HBA card.
I already successful setup truenas and run weekly backup. However I felt truenas offer a lot of stuff that I don't need. I decide to give openmediavault a shot, and I prefer open media vault web gui better. Since I use mobile rack for the system drive, it was easy to swtich between truenas and open media vault.
I installed open media vault on another ssd, I played around the file sytem abit. First I installed MD and setup drives with software raid 5 and use Btrfs as file system. Than I installed extra plug-in, installed zfs plugin. setup raidz with 1z4 compression. (extraclly same seutp as Truenas.)
Everything seem go smoothly, I can run synology hyper backup fine with raid5 or with zfs plugin. however I notice the file trasnfer speed is noticeable slower with open media vault. With Truenas I am getting 70~100 MB/s (mostly 90mb/s) trasnfer speed with hyper backup, however I am only getting 30~70mb/s (mostly 50mb/s) with open media vault no matter if it is btrfs on top of raid 5 or raidz1 zfs.
I noticed truenas will use almost all system memory for ZFS cache (31.7g total memory. service 4.4g, zfs cache 26.5g, 0.7 g free.) while open media vault rarely used more than 50% system memory. Does ZFS cahce sisze really effect how fast hyper backup trasnfer files? I thought about increase zfs arch size, but for someone not used to linux/unit, it really a lot more complicated. Is there easier way to do so?
