diff --git a/modules/monitoring.nix b/modules/monitoring.nix
index e5b13f1..7865202 100644
--- a/modules/monitoring.nix
+++ b/modules/monitoring.nix
@@ -60,6 +60,21 @@
       fi
     done
   '';
+
+  # Physical pool IOPS/bandwidth straight from the vdev layer. The telegraf
+  # `inputs.zfs` poolMetrics emits per-objset *logical* counters, which include
+  # ARC cache hits — so RAM-served reads show up as huge "pool IOPS" with zero
+  # actual disk activity (this misled a 2026-05-30 mountd investigation). This
+  # collector reports what `zpool iostat` reports: real disk ops. The second
+  # block of `iostat 1 2` is the live 1s sample; the operations columns are
+  # already per-second rates, so these are gauges (no derivative in Grafana).
+  zpoolIostatScript = pkgs.writeShellScript "zpool-iostat" ''
+    npools=$(${pkgs.zfs}/bin/zpool list -H -o name | ${pkgs.coreutils}/bin/wc -l)
+    ${pkgs.zfs}/bin/zpool iostat -Hp 1 2 | ${pkgs.coreutils}/bin/tail -n "$npools" \
+      | while read -r name alloc free rops wops rbytes wbytes; do
+        echo "zpool_io,pool=$name read_ops=''${rops}i,write_ops=''${wops}i,read_bytes=''${rbytes}i,write_bytes=''${wbytes}i"
+      done
+  '';
 in {
   options.skyworks.monitoring = {
     enable = lib.mkEnableOption "Telegraf monitoring to InfluxDB";
@@ -151,6 +166,14 @@
               timeout = "60s";
               data_format = "influx";
             }
+            {
+              # Physical pool IOPS (measurement `zpool_io`) — the honest version
+              # of the ARC-inclusive `zfs` poolMetrics counters.
+              commands = [ "${zpoolIostatScript}" ];
+              interval = "10s";
+              timeout = "10s";
+              data_format = "influx";
+            }
           ];
         };
       };