diff options
| -rw-r--r-- | man/man5/zfs-module-parameters.5 | 12 | ||||
| -rw-r--r-- | module/zfs/arc.c | 16 |
2 files changed, 26 insertions, 2 deletions
diff --git a/man/man5/zfs-module-parameters.5 b/man/man5/zfs-module-parameters.5 index 0444d9050..5b6eb7afd 100644 --- a/man/man5/zfs-module-parameters.5 +++ b/man/man5/zfs-module-parameters.5 @@ -524,6 +524,18 @@ Default value: \fB8\fR. .sp .ne 2 .na + +\fBzfs_arc_p_min_shift\fR (int) +.ad +.RS 12n +arc_c shift to calc min/max arc_p +.sp +Default value: \fB4\fR. +.RE + +.sp +.ne 2 +.na \fBzfs_arc_p_aggressive_disable\fR (int) .ad .RS 12n diff --git a/module/zfs/arc.c b/module/zfs/arc.c index aaf268264..2661bc8a7 100644 --- a/module/zfs/arc.c +++ b/module/zfs/arc.c @@ -188,6 +188,9 @@ static int arc_grow_retry = 5; /* shift of arc_c for calculating overflow limit in arc_get_data_buf */ int zfs_arc_overflow_shift = 8; +/* shift of arc_c for calculating both min and max arc_p */ +static int arc_p_min_shift = 4; + /* log2(fraction of arc to reclaim) */ static int arc_shrink_shift = 7; @@ -230,6 +233,7 @@ unsigned long zfs_arc_meta_limit = 0; unsigned long zfs_arc_meta_min = 0; int zfs_arc_grow_retry = 0; int zfs_arc_shrink_shift = 0; +int zfs_arc_p_min_shift = 0; int zfs_disable_dup_eviction = 0; int zfs_arc_average_blocksize = 8 * 1024; /* 8KB */ @@ -3718,6 +3722,7 @@ static void arc_adapt(int bytes, arc_state_t *state) { int mult; + uint64_t arc_p_min = (arc_c >> arc_p_min_shift); int64_t mrug_size = refcount_count(&arc_mru_ghost->arcs_size); int64_t mfug_size = refcount_count(&arc_mfu_ghost->arcs_size); @@ -3738,7 +3743,7 @@ arc_adapt(int bytes, arc_state_t *state) if (!zfs_arc_p_dampener_disable) mult = MIN(mult, 10); /* avoid wild arc_p adjustment */ - arc_p = MIN(arc_c, arc_p + bytes * mult); + arc_p = MIN(arc_c - arc_p_min, arc_p + bytes * mult); } else if (state == arc_mfu_ghost) { uint64_t delta; @@ -3747,7 +3752,7 @@ arc_adapt(int bytes, arc_state_t *state) mult = MIN(mult, 10); delta = MIN(bytes * mult, arc_p); - arc_p = MAX(0, arc_p - delta); + arc_p = MAX(arc_p_min, arc_p - delta); } ASSERT((int64_t)arc_p >= 0); @@ -5265,6 +5270,10 @@ arc_tuning_update(void) arc_no_grow_shift = MIN(arc_no_grow_shift, arc_shrink_shift -1); } + /* Valid range: 1 - N */ + if (zfs_arc_p_min_shift) + arc_p_min_shift = zfs_arc_p_min_shift; + /* Valid range: 1 - N ticks */ if (zfs_arc_min_prefetch_lifespan) arc_min_prefetch_lifespan = zfs_arc_min_prefetch_lifespan; @@ -6996,6 +7005,9 @@ MODULE_PARM_DESC(zfs_arc_p_dampener_disable, "disable arc_p adapt dampener"); module_param(zfs_arc_shrink_shift, int, 0644); MODULE_PARM_DESC(zfs_arc_shrink_shift, "log2(fraction of arc to reclaim)"); +module_param(zfs_arc_p_min_shift, int, 0644); +MODULE_PARM_DESC(zfs_arc_p_min_shift, "arc_c shift to calc min/max arc_p"); + module_param(zfs_disable_dup_eviction, int, 0644); MODULE_PARM_DESC(zfs_disable_dup_eviction, "disable duplicate buffer eviction"); |