Openzfs l2arc code#

RaidZ: uses a distributed parity code to allow a number of disks to fail before losing data, up to three, and that number is appended to RaidZ forming the names RaidZ1 RaidZ2 and RaidZ3. RaidZ vdevs are fixed, and once created, they cannot have additional disks added or removed.

Mirror: Mirror vdevs provide the gold standard of redundancy and high speed by pairing disks. They resilver faster, and are more flexible, including allowing the pool to shrink.

Stripe: It’s possible to construct a vdev from a single drive, called a stripe any disk losses will result in the loss of the entire pool.

A vdev is responsible for providing data protection, to allow the pool to suffer individual disk losses without losing data. Disks can be combined into vdevs, or virtual devices, which are the leaves of the storage hierarchy. So now you have some disks and are ready to try ZFS, you should understand the hierarchy of the ZFS storage architecture. The hierarchy of disks, vdevs, pools, datasets: The FreeBSD installer has an interface allowing ZFS as the root file system, allowing a bootable FreeBSD system on ZFS. Selecting the guided root on ZFS, install will permit graphical selection of disks to include in a pool. This is an easy way to explore ZFS features without an extensive hardware investment.

This article will introduce new users to ZFS, and cover some of the new features in the upgrade. rest of stuff-> primarycache=none secondarycache=metadataīut then I realize, that the second category can be divided further to 'I need it as fast as possible' (Nextcloud) and 'just don't be annoyingly slow' (Ocasional gaming on my vm).Īnd just to be clear, nextcloud is NOT used more often I just want to prioritize ARC to hold as much Nextcloud data in ram as possible and in the same time cache game data on NVME, because more annoying for me is slow nextcluod, then a little bit longer loading times of some games.FreeBSD 13.0 imported OpenZFS 2.0 replacing the bespoke port that had served since 2007.VM -> primarycache=all secondarycache=all.Nextcloud -> primarycache=all secondarycache=all.I decided to disable cache for first group and enable for rest. The workload I have can be split into basically two main categories, write a lot of data/read almost none of it or read once (zoneminder/plex/backups) and write once/read multiple times (games on VM/nextcloud) The whole system is used mainly for Nextcloud, Plex, zoneminder and some Virtualization (GPU passthrough to a Windows10 vm, some other stuff) so nothing really special (please notice no torrent)īecause some of my use cases require load of ram to work (VM/Zoneminder) I have limited resources for ZFS caches (and as for now no plan to extend RAM) so I want to squeeze as much performance as possible from the HW I currently own.

Openzfs l2arc free#

NAME SIZE ALLOC FREE CKPOINT EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT I Have a 'home lab' system (Ubuntu 22.04 on i3-9300 with 32G ecc-ram, 10G of witch is dedicated to hugepages) currently holding 2 zfs raidz1 pools, one with 3x2TB WD-RED and nvme as log and cache device, and the second one with 3x1TB HDD (planing to extend this one to 3x12TB) currently used as backup only zpool list -v