On Sat, 22 Jul 2023 07:55:41 -0400, Greg Troxel wrote: > Using half the ram for pools feels like perhaps a bug, depending -- even > if you are getting away with it. > > I am curious: > > What VM approach?
An nvmm accelerated qemu > How much ram in the domU (generic term even if not xen)? 800 MB > Are you using NFS from the domU to dom0? domU running zfs? Something > else? The machine is not running Xen - I found the Dom0 too limiting for the purpose. It has a pair of SSDs (older intel SLC sata) for system partitions and L2ARC, and a pair of 4TB Seagate IronWolf disks for zfs storage, exported through nfs, afp, smb. The VM nfs-mounts pkgsrc and distfiles from the base machine. > Is the 16G for pools the sum of the dom0 and domU pools? Or ? That is for the base machine, so yes. >> My guess would be that your 8 GB are simply not enough for sustaining >> both zfs and builds. > > I think that's how it is, but it seems obviously buggy for that to be > the case. It is dysfunctional to run the system to lockup caching > things that don't need to be cached. The ffs vnode cache for example > does not do this. Agreed. But zfs has had a reputation of being memory-hungry for ~ever. And to my understanding NetBSD's zfs version is not exactly state of the art. > The zfs howto currently talks about zfs taking 1G plus 1G per 1T of > disk. For me that would be 1.8G, which would be ok. But that's not > what happens. I wonder: How much memory are you assigning to the Dom0? That alone would increase memory pressure compared to a native kernel. > Thanks for the data point; I'll probably edit the zfs HOWTO. As it is > we should probably be recommending against zfs unless you have 64G of > RAM :-( as even your system doesn't seem healthy memory usage wise. That sounds overly pessimistic to me. I have run a department fileserver with dozens of clients (home on NFS) on 32 GB RAM for years - the same hardware that now serves as file and build server under NetBSD - without ever running into zfs related memory issues. Your 8 GB machine would probably be just fine with zfs as a pure fileserver. Cheerio, Hauke -- The ASCII Ribbon Campaign Hauke Fath () No HTML/RTF in email Institut für Nachrichtentechnik /\ No Word docs in email TU Darmstadt Respect for open standards Ruf +49-6151-16-21344