Make arc+l2arc module options writable

The l2arc module options can be made safely writable.  This allows
the options to be changed without unloading/loading the modules.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This commit is contained in:
Brian Behlendorf 2013-07-24 10:14:11 -07:00
parent c93504f03a
commit bce45ec9fb

View File

@ -148,7 +148,7 @@ static kcondvar_t arc_reclaim_thr_cv; /* used to signal reclaim thr */
static uint8_t arc_thread_exit; static uint8_t arc_thread_exit;
/* number of bytes to prune from caches when at arc_meta_limit is reached */ /* number of bytes to prune from caches when at arc_meta_limit is reached */
uint_t arc_meta_prune = 1048576; int zfs_arc_meta_prune = 1048576;
typedef enum arc_reclaim_strategy { typedef enum arc_reclaim_strategy {
ARC_RECLAIM_AGGR, /* Aggressive reclaim strategy */ ARC_RECLAIM_AGGR, /* Aggressive reclaim strategy */
@ -156,25 +156,31 @@ typedef enum arc_reclaim_strategy {
} arc_reclaim_strategy_t; } arc_reclaim_strategy_t;
/* number of seconds before growing cache again */ /* number of seconds before growing cache again */
static int arc_grow_retry = 5; int zfs_arc_grow_retry = 5;
/* expiration time for arc_no_grow */
static clock_t arc_grow_time = 0;
/* shift of arc_c for calculating both min and max arc_p */ /* shift of arc_c for calculating both min and max arc_p */
static int arc_p_min_shift = 4; int zfs_arc_p_min_shift = 4;
/* log2(fraction of arc to reclaim) */ /* log2(fraction of arc to reclaim) */
static int arc_shrink_shift = 5; int zfs_arc_shrink_shift = 5;
/* /*
* minimum lifespan of a prefetch block in clock ticks * minimum lifespan of a prefetch block in clock ticks
* (initialized in arc_init()) * (initialized in arc_init())
*/ */
static int arc_min_prefetch_lifespan; int zfs_arc_min_prefetch_lifespan = HZ;
/* disable arc proactive arc throttle due to low memory */
int zfs_arc_memory_throttle_disable = 1;
/* disable duplicate buffer eviction */
int zfs_disable_dup_eviction = 0;
static int arc_dead; static int arc_dead;
/* expiration time for arc_no_grow */
static clock_t arc_grow_time = 0;
/* /*
* The arc has filled available memory and has now warmed up. * The arc has filled available memory and has now warmed up.
*/ */
@ -186,12 +192,6 @@ static boolean_t arc_warm;
unsigned long zfs_arc_max = 0; unsigned long zfs_arc_max = 0;
unsigned long zfs_arc_min = 0; unsigned long zfs_arc_min = 0;
unsigned long zfs_arc_meta_limit = 0; unsigned long zfs_arc_meta_limit = 0;
int zfs_arc_grow_retry = 0;
int zfs_arc_shrink_shift = 0;
int zfs_arc_p_min_shift = 0;
int zfs_arc_memory_throttle_disable = 1;
int zfs_disable_dup_eviction = 0;
int zfs_arc_meta_prune = 0;
/* /*
* Note that buffers can be in one of 6 states: * Note that buffers can be in one of 6 states:
@ -1761,7 +1761,7 @@ arc_evict(arc_state_t *state, uint64_t spa, int64_t bytes, boolean_t recycle,
(spa && ab->b_spa != spa) || (spa && ab->b_spa != spa) ||
(ab->b_flags & (ARC_PREFETCH|ARC_INDIRECT) && (ab->b_flags & (ARC_PREFETCH|ARC_INDIRECT) &&
ddi_get_lbolt() - ab->b_arc_access < ddi_get_lbolt() - ab->b_arc_access <
arc_min_prefetch_lifespan)) { zfs_arc_min_prefetch_lifespan)) {
skipped++; skipped++;
continue; continue;
} }
@ -2112,7 +2112,7 @@ arc_adjust_meta(int64_t adjustment, boolean_t may_prune)
} }
if (may_prune && (adjustment > 0) && (arc_meta_used > arc_meta_limit)) if (may_prune && (adjustment > 0) && (arc_meta_used > arc_meta_limit))
arc_do_user_prune(arc_meta_prune); arc_do_user_prune(zfs_arc_meta_prune);
} }
/* /*
@ -2163,14 +2163,14 @@ arc_shrink(uint64_t bytes)
if (arc_c > arc_c_min) { if (arc_c > arc_c_min) {
uint64_t to_free; uint64_t to_free;
to_free = bytes ? bytes : arc_c >> arc_shrink_shift; to_free = bytes ? bytes : arc_c >> zfs_arc_shrink_shift;
if (arc_c > arc_c_min + to_free) if (arc_c > arc_c_min + to_free)
atomic_add_64(&arc_c, -to_free); atomic_add_64(&arc_c, -to_free);
else else
arc_c = arc_c_min; arc_c = arc_c_min;
atomic_add_64(&arc_p, -(arc_p >> arc_shrink_shift)); atomic_add_64(&arc_p, -(arc_p >> zfs_arc_shrink_shift));
if (arc_c > arc_size) if (arc_c > arc_size)
arc_c = MAX(arc_size, arc_c_min); arc_c = MAX(arc_size, arc_c_min);
if (arc_p > arc_c) if (arc_p > arc_c)
@ -2249,7 +2249,7 @@ arc_adapt_thread(void)
} }
/* reset the growth delay for every reclaim */ /* reset the growth delay for every reclaim */
arc_grow_time = ddi_get_lbolt()+(arc_grow_retry * hz); arc_grow_time = ddi_get_lbolt()+(zfs_arc_grow_retry * hz);
arc_kmem_reap_now(last_reclaim, 0); arc_kmem_reap_now(last_reclaim, 0);
arc_warm = B_TRUE; arc_warm = B_TRUE;
@ -2279,6 +2279,26 @@ arc_adapt_thread(void)
(void) cv_timedwait_interruptible(&arc_reclaim_thr_cv, (void) cv_timedwait_interruptible(&arc_reclaim_thr_cv,
&arc_reclaim_thr_lock, (ddi_get_lbolt() + hz)); &arc_reclaim_thr_lock, (ddi_get_lbolt() + hz));
CALLB_CPR_SAFE_END(&cpr, &arc_reclaim_thr_lock); CALLB_CPR_SAFE_END(&cpr, &arc_reclaim_thr_lock);
/* Allow the module options to be changed */
if (zfs_arc_max > 64 << 20 &&
zfs_arc_max < physmem * PAGESIZE &&
zfs_arc_max != arc_c_max)
arc_c_max = zfs_arc_max;
if (zfs_arc_min > 0 &&
zfs_arc_min < arc_c_max &&
zfs_arc_min != arc_c_min)
arc_c_min = zfs_arc_min;
if (zfs_arc_meta_limit > 0 &&
zfs_arc_meta_limit <= arc_c_max &&
zfs_arc_meta_limit != arc_meta_limit)
arc_meta_limit = zfs_arc_meta_limit;
} }
arc_thread_exit = 0; arc_thread_exit = 0;
@ -2399,7 +2419,7 @@ __arc_shrinker_func(struct shrinker *shrink, struct shrink_control *sc)
ARCSTAT_BUMP(arcstat_memory_indirect_count); ARCSTAT_BUMP(arcstat_memory_indirect_count);
} else { } else {
arc_no_grow = B_TRUE; arc_no_grow = B_TRUE;
arc_grow_time = ddi_get_lbolt() + (arc_grow_retry * hz); arc_grow_time = ddi_get_lbolt() + (zfs_arc_grow_retry * hz);
ARCSTAT_BUMP(arcstat_memory_direct_count); ARCSTAT_BUMP(arcstat_memory_direct_count);
} }
@ -2421,7 +2441,7 @@ static void
arc_adapt(int bytes, arc_state_t *state) arc_adapt(int bytes, arc_state_t *state)
{ {
int mult; int mult;
uint64_t arc_p_min = (arc_c >> arc_p_min_shift); uint64_t arc_p_min = (arc_c >> zfs_arc_p_min_shift);
if (state == arc_l2c_only) if (state == arc_l2c_only)
return; return;
@ -3756,7 +3776,7 @@ arc_init(void)
cv_init(&arc_reclaim_thr_cv, NULL, CV_DEFAULT, NULL); cv_init(&arc_reclaim_thr_cv, NULL, CV_DEFAULT, NULL);
/* Convert seconds to clock ticks */ /* Convert seconds to clock ticks */
arc_min_prefetch_lifespan = 1 * hz; zfs_arc_min_prefetch_lifespan = 1 * hz;
/* Start out with 1/8 of all memory */ /* Start out with 1/8 of all memory */
arc_c = physmem * PAGESIZE / 8; arc_c = physmem * PAGESIZE / 8;
@ -3804,18 +3824,6 @@ arc_init(void)
if (arc_c_min < arc_meta_limit / 2 && zfs_arc_min == 0) if (arc_c_min < arc_meta_limit / 2 && zfs_arc_min == 0)
arc_c_min = arc_meta_limit / 2; arc_c_min = arc_meta_limit / 2;
if (zfs_arc_grow_retry > 0)
arc_grow_retry = zfs_arc_grow_retry;
if (zfs_arc_shrink_shift > 0)
arc_shrink_shift = zfs_arc_shrink_shift;
if (zfs_arc_p_min_shift > 0)
arc_p_min_shift = zfs_arc_p_min_shift;
if (zfs_arc_meta_prune > 0)
arc_meta_prune = zfs_arc_meta_prune;
/* if kmem_flags are set, lets try to use less memory */ /* if kmem_flags are set, lets try to use less memory */
if (kmem_debugging()) if (kmem_debugging())
arc_c = arc_c / 2; arc_c = arc_c / 2;
@ -5013,25 +5021,25 @@ EXPORT_SYMBOL(arc_getbuf_func);
EXPORT_SYMBOL(arc_add_prune_callback); EXPORT_SYMBOL(arc_add_prune_callback);
EXPORT_SYMBOL(arc_remove_prune_callback); EXPORT_SYMBOL(arc_remove_prune_callback);
module_param(zfs_arc_min, ulong, 0444); module_param(zfs_arc_min, ulong, 0644);
MODULE_PARM_DESC(zfs_arc_min, "Min arc size"); MODULE_PARM_DESC(zfs_arc_min, "Min arc size");
module_param(zfs_arc_max, ulong, 0444); module_param(zfs_arc_max, ulong, 0644);
MODULE_PARM_DESC(zfs_arc_max, "Max arc size"); MODULE_PARM_DESC(zfs_arc_max, "Max arc size");
module_param(zfs_arc_meta_limit, ulong, 0444); module_param(zfs_arc_meta_limit, ulong, 0644);
MODULE_PARM_DESC(zfs_arc_meta_limit, "Meta limit for arc size"); MODULE_PARM_DESC(zfs_arc_meta_limit, "Meta limit for arc size");
module_param(zfs_arc_meta_prune, int, 0444); module_param(zfs_arc_meta_prune, int, 0644);
MODULE_PARM_DESC(zfs_arc_meta_prune, "Bytes of meta data to prune"); MODULE_PARM_DESC(zfs_arc_meta_prune, "Bytes of meta data to prune");
module_param(zfs_arc_grow_retry, int, 0444); module_param(zfs_arc_grow_retry, int, 0644);
MODULE_PARM_DESC(zfs_arc_grow_retry, "Seconds before growing arc size"); MODULE_PARM_DESC(zfs_arc_grow_retry, "Seconds before growing arc size");
module_param(zfs_arc_shrink_shift, int, 0444); module_param(zfs_arc_shrink_shift, int, 0644);
MODULE_PARM_DESC(zfs_arc_shrink_shift, "log2(fraction of arc to reclaim)"); MODULE_PARM_DESC(zfs_arc_shrink_shift, "log2(fraction of arc to reclaim)");
module_param(zfs_arc_p_min_shift, int, 0444); 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_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_param(zfs_disable_dup_eviction, int, 0644);
@ -5040,28 +5048,31 @@ MODULE_PARM_DESC(zfs_disable_dup_eviction, "disable duplicate buffer eviction");
module_param(zfs_arc_memory_throttle_disable, int, 0644); module_param(zfs_arc_memory_throttle_disable, int, 0644);
MODULE_PARM_DESC(zfs_arc_memory_throttle_disable, "disable memory throttle"); MODULE_PARM_DESC(zfs_arc_memory_throttle_disable, "disable memory throttle");
module_param(l2arc_write_max, ulong, 0444); module_param(zfs_arc_min_prefetch_lifespan, int, 0644);
MODULE_PARM_DESC(zfs_arc_min_prefetch_lifespan, "Min life of prefetch block");
module_param(l2arc_write_max, ulong, 0644);
MODULE_PARM_DESC(l2arc_write_max, "Max write bytes per interval"); MODULE_PARM_DESC(l2arc_write_max, "Max write bytes per interval");
module_param(l2arc_write_boost, ulong, 0444); module_param(l2arc_write_boost, ulong, 0644);
MODULE_PARM_DESC(l2arc_write_boost, "Extra write bytes during device warmup"); MODULE_PARM_DESC(l2arc_write_boost, "Extra write bytes during device warmup");
module_param(l2arc_headroom, ulong, 0444); module_param(l2arc_headroom, ulong, 0644);
MODULE_PARM_DESC(l2arc_headroom, "Number of max device writes to precache"); MODULE_PARM_DESC(l2arc_headroom, "Number of max device writes to precache");
module_param(l2arc_feed_secs, ulong, 0444); module_param(l2arc_feed_secs, ulong, 0644);
MODULE_PARM_DESC(l2arc_feed_secs, "Seconds between L2ARC writing"); MODULE_PARM_DESC(l2arc_feed_secs, "Seconds between L2ARC writing");
module_param(l2arc_feed_min_ms, ulong, 0444); module_param(l2arc_feed_min_ms, ulong, 0644);
MODULE_PARM_DESC(l2arc_feed_min_ms, "Min feed interval in milliseconds"); MODULE_PARM_DESC(l2arc_feed_min_ms, "Min feed interval in milliseconds");
module_param(l2arc_noprefetch, int, 0444); module_param(l2arc_noprefetch, int, 0644);
MODULE_PARM_DESC(l2arc_noprefetch, "Skip caching prefetched buffers"); MODULE_PARM_DESC(l2arc_noprefetch, "Skip caching prefetched buffers");
module_param(l2arc_feed_again, int, 0444); module_param(l2arc_feed_again, int, 0644);
MODULE_PARM_DESC(l2arc_feed_again, "Turbo L2ARC warmup"); MODULE_PARM_DESC(l2arc_feed_again, "Turbo L2ARC warmup");
module_param(l2arc_norw, int, 0444); module_param(l2arc_norw, int, 0644);
MODULE_PARM_DESC(l2arc_norw, "No reads during writes"); MODULE_PARM_DESC(l2arc_norw, "No reads during writes");
#endif #endif