Add arc_state_t stats to arcstats

To ensure the arc is behaving properly we need greater visibility
in to exactly how it's managing the systems memory.  This patch
takes one step in that direction be adding the current arc_state_t
for the anon, mru, mru_ghost, mfu, and mfs_ghost lists.  The l2
arc_state_t is already well represented in the arcstats.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

diff --git a/module/zfs/arc.c b/module/zfs/arc.c
index 2220c4d..cfd4c79 100644 (file)
--- a/module/zfs/arc.c
+++ b/module/zfs/arc.c
@@ -271,6 +271,21 @@ typedef struct arc_stats {
        kstat_named_t arcstat_hdr_size;
        kstat_named_t arcstat_data_size;
        kstat_named_t arcstat_other_size;
+       kstat_named_t arcstat_anon_size;
+       kstat_named_t arcstat_anon_evict_data;
+       kstat_named_t arcstat_anon_evict_metadata;
+       kstat_named_t arcstat_mru_size;
+       kstat_named_t arcstat_mru_evict_data;
+       kstat_named_t arcstat_mru_evict_metadata;
+       kstat_named_t arcstat_mru_ghost_size;
+       kstat_named_t arcstat_mru_ghost_evict_data;
+       kstat_named_t arcstat_mru_ghost_evict_metadata;
+       kstat_named_t arcstat_mfu_size;
+       kstat_named_t arcstat_mfu_evict_data;
+       kstat_named_t arcstat_mfu_evict_metadata;
+       kstat_named_t arcstat_mfu_ghost_size;
+       kstat_named_t arcstat_mfu_ghost_evict_data;
+       kstat_named_t arcstat_mfu_ghost_evict_metadata;
        kstat_named_t arcstat_l2_hits;
        kstat_named_t arcstat_l2_misses;
        kstat_named_t arcstat_l2_feeds;
@@ -336,6 +351,21 @@ static arc_stats_t arc_stats = {
        { "hdr_size",                   KSTAT_DATA_UINT64 },
        { "data_size",                  KSTAT_DATA_UINT64 },
        { "other_size",                 KSTAT_DATA_UINT64 },
+       { "anon_size",                  KSTAT_DATA_UINT64 },
+       { "anon_evict_data",            KSTAT_DATA_UINT64 },
+       { "anon_evict_metadata",        KSTAT_DATA_UINT64 },
+       { "mru_size",                   KSTAT_DATA_UINT64 },
+       { "mru_evict_data",             KSTAT_DATA_UINT64 },
+       { "mru_evict_metadata",         KSTAT_DATA_UINT64 },
+       { "mru_ghost_size",             KSTAT_DATA_UINT64 },
+       { "mru_ghost_evict_data",       KSTAT_DATA_UINT64 },
+       { "mru_ghost_evict_metadata",   KSTAT_DATA_UINT64 },
+       { "mfu_size",                   KSTAT_DATA_UINT64 },
+       { "mfu_evict_data",             KSTAT_DATA_UINT64 },
+       { "mfu_evict_metadata",         KSTAT_DATA_UINT64 },
+       { "mfu_ghost_size",             KSTAT_DATA_UINT64 },
+       { "mfu_ghost_evict_data",       KSTAT_DATA_UINT64 },
+       { "mfu_ghost_evict_metadata",   KSTAT_DATA_UINT64 },
        { "l2_hits",                    KSTAT_DATA_UINT64 },
        { "l2_misses",                  KSTAT_DATA_UINT64 },
        { "l2_feeds",                   KSTAT_DATA_UINT64 },
@@ -3639,6 +3669,48 @@ arc_tempreserve_space(uint64_t reserve, uint64_t txg)
        return (0);
 }
 
+static void
+arc_kstat_update_state(arc_state_t *state, kstat_named_t *size,
+    kstat_named_t *evict_data, kstat_named_t *evict_metadata)
+{
+       size->value.ui64 = state->arcs_size;
+       evict_data->value.ui64 = state->arcs_lsize[ARC_BUFC_DATA];
+       evict_metadata->value.ui64 = state->arcs_lsize[ARC_BUFC_METADATA];
+}
+
+static int
+arc_kstat_update(kstat_t *ksp, int rw)
+{
+       arc_stats_t *as = ksp->ks_data;
+
+       if (rw == KSTAT_WRITE) {
+               return (EACCES);
+       } else {
+               arc_kstat_update_state(arc_anon,
+                   &as->arcstat_anon_size,
+                   &as->arcstat_anon_evict_data,
+                   &as->arcstat_anon_evict_metadata);
+               arc_kstat_update_state(arc_mru,
+                   &as->arcstat_mru_size,
+                   &as->arcstat_mru_evict_data,
+                   &as->arcstat_mru_evict_metadata);
+               arc_kstat_update_state(arc_mru_ghost,
+                   &as->arcstat_mru_ghost_size,
+                   &as->arcstat_mru_ghost_evict_data,
+                   &as->arcstat_mru_ghost_evict_metadata);
+               arc_kstat_update_state(arc_mfu,
+                   &as->arcstat_mfu_size,
+                   &as->arcstat_mfu_evict_data,
+                   &as->arcstat_mfu_evict_metadata);
+               arc_kstat_update_state(arc_mru_ghost,
+                   &as->arcstat_mfu_ghost_size,
+                   &as->arcstat_mfu_ghost_evict_data,
+                   &as->arcstat_mfu_ghost_evict_metadata);
+       }
+
+       return (0);
+}
+
 void
 arc_init(void)
 {
@@ -3767,6 +3839,7 @@ arc_init(void)
 
        if (arc_ksp != NULL) {
                arc_ksp->ks_data = &arc_stats;
+               arc_ksp->ks_update = arc_kstat_update;
                kstat_install(arc_ksp);
        }