zfs: Manage swap volume properties

manifests/base/bootloader.pp

@@ -20,6 +20,7 @@ class nest::base::bootloader {
     # Physical swap is still useful for hibernation.
     #
     # See: https://github.com/openzfs/zfs/issues/7734
+    # See also: nest::base::zfs for workarounds
     'zswap.enabled=1',
     'zswap.compressor=lzo-rle',
     'zswap.zpool=z3fold',

manifests/base/zfs.pp

@@ -112,4 +112,16 @@ class nest::base::zfs {
   }
 
   ::nest::lib::systemd_reload { 'zfs': }
+
+  unless $facts['virtual'] == 'lxc' {
+    # Manage swap volume properties for experimenting with workarounds listed in
+    # https://github.com/openzfs/zfs/issues/7734
+    zfs { "${facts['rpool']}/swap":
+      compression    => 'off',
+      sync           => 'always',
+      primarycache   => 'metadata',
+      secondarycache => 'none',
+      logbias        => 'throughput',
+    }
+  }
 }