On Thu, 27 Jul 2023 06:43:45 -0400
Greg Troxel <g...@lexort.com> wrote:
> Thus it seems there is a limit for zfs usage, but it is simply
> sometimes too high depending on available RAM.
I use this patch on my RPi4, which I feel improves things.
People might find it helpful.
There ought to be writable sysctl knobs for some of the ZFS
tuneables, but looks like it isn't implemented in NetBSD yet.
--- external/cddl/osnet/dist/uts/common/fs/zfs/arc.c 3 Aug 2022 01:53:06
-0000 1.22
+++ external/cddl/osnet/dist/uts/common/fs/zfs/arc.c 27 Jul 2023 11:10:40
-0000
@@ -6100,6 +6100,10 @@ arc_init(void)
else
arc_c_max = arc_c_min;
arc_c_max = MAX(arc_c * 5, arc_c_max);
+#if defined(__NetBSD__) && defined(_KERNEL)
+/* XXX prevent ARC from eating more than 12% of kmem */
+ arc_c_max = MIN(arc_c, vmem_size(heap_arena, VMEM_ALLOC | VMEM_FREE) /
8);
+#endif
/*
* In userland, there's only the memory pressure that we artificially
