summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/md/bcache/bcache.h4
-rw-r--r--drivers/md/bcache/sysfs.c23
-rw-r--r--drivers/md/bcache/writeback.c42
-rw-r--r--drivers/md/bcache/writeback.h4
4 files changed, 73 insertions, 0 deletions
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 1d57f48307e6..d7a84327b7f1 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -373,6 +373,7 @@ struct cached_dev {
unsigned int partial_stripes_expensive:1;
unsigned int writeback_metadata:1;
unsigned int writeback_running:1;
+ unsigned int writeback_consider_fragment:1;
unsigned char writeback_percent;
unsigned int writeback_delay;
@@ -385,6 +386,9 @@ struct cached_dev {
unsigned int writeback_rate_update_seconds;
unsigned int writeback_rate_i_term_inverse;
unsigned int writeback_rate_p_term_inverse;
+ unsigned int writeback_rate_fp_term_low;
+ unsigned int writeback_rate_fp_term_mid;
+ unsigned int writeback_rate_fp_term_high;
unsigned int writeback_rate_minimum;
enum stop_on_failure stop_when_cache_set_failed;
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 00a520c03f41..eef15f8022ba 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -117,10 +117,14 @@ rw_attribute(writeback_running);
rw_attribute(writeback_percent);
rw_attribute(writeback_delay);
rw_attribute(writeback_rate);
+rw_attribute(writeback_consider_fragment);
rw_attribute(writeback_rate_update_seconds);
rw_attribute(writeback_rate_i_term_inverse);
rw_attribute(writeback_rate_p_term_inverse);
+rw_attribute(writeback_rate_fp_term_low);
+rw_attribute(writeback_rate_fp_term_mid);
+rw_attribute(writeback_rate_fp_term_high);
rw_attribute(writeback_rate_minimum);
read_attribute(writeback_rate_debug);
@@ -195,6 +199,7 @@ SHOW(__bch_cached_dev)
var_printf(bypass_torture_test, "%i");
var_printf(writeback_metadata, "%i");
var_printf(writeback_running, "%i");
+ var_printf(writeback_consider_fragment, "%i");
var_print(writeback_delay);
var_print(writeback_percent);
sysfs_hprint(writeback_rate,
@@ -205,6 +210,9 @@ SHOW(__bch_cached_dev)
var_print(writeback_rate_update_seconds);
var_print(writeback_rate_i_term_inverse);
var_print(writeback_rate_p_term_inverse);
+ var_print(writeback_rate_fp_term_low);
+ var_print(writeback_rate_fp_term_mid);
+ var_print(writeback_rate_fp_term_high);
var_print(writeback_rate_minimum);
if (attr == &sysfs_writeback_rate_debug) {
@@ -303,6 +311,7 @@ STORE(__cached_dev)
sysfs_strtoul_bool(bypass_torture_test, dc->bypass_torture_test);
sysfs_strtoul_bool(writeback_metadata, dc->writeback_metadata);
sysfs_strtoul_bool(writeback_running, dc->writeback_running);
+ sysfs_strtoul_bool(writeback_consider_fragment, dc->writeback_consider_fragment);
sysfs_strtoul_clamp(writeback_delay, dc->writeback_delay, 0, UINT_MAX);
sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent,
@@ -331,6 +340,16 @@ STORE(__cached_dev)
sysfs_strtoul_clamp(writeback_rate_p_term_inverse,
dc->writeback_rate_p_term_inverse,
1, UINT_MAX);
+ sysfs_strtoul_clamp(writeback_rate_fp_term_low,
+ dc->writeback_rate_fp_term_low,
+ 1, dc->writeback_rate_fp_term_mid - 1);
+ sysfs_strtoul_clamp(writeback_rate_fp_term_mid,
+ dc->writeback_rate_fp_term_mid,
+ dc->writeback_rate_fp_term_low + 1,
+ dc->writeback_rate_fp_term_high - 1);
+ sysfs_strtoul_clamp(writeback_rate_fp_term_high,
+ dc->writeback_rate_fp_term_high,
+ dc->writeback_rate_fp_term_mid + 1, UINT_MAX);
sysfs_strtoul_clamp(writeback_rate_minimum,
dc->writeback_rate_minimum,
1, UINT_MAX);
@@ -499,9 +518,13 @@ static struct attribute *bch_cached_dev_files[] = {
&sysfs_writeback_delay,
&sysfs_writeback_percent,
&sysfs_writeback_rate,
+ &sysfs_writeback_consider_fragment,
&sysfs_writeback_rate_update_seconds,
&sysfs_writeback_rate_i_term_inverse,
&sysfs_writeback_rate_p_term_inverse,
+ &sysfs_writeback_rate_fp_term_low,
+ &sysfs_writeback_rate_fp_term_mid,
+ &sysfs_writeback_rate_fp_term_high,
&sysfs_writeback_rate_minimum,
&sysfs_writeback_rate_debug,
&sysfs_io_errors,
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index a129e4d2707c..82d4e0880a99 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -88,6 +88,44 @@ static void __update_writeback_rate(struct cached_dev *dc)
int64_t integral_scaled;
uint32_t new_rate;
+ /*
+ * We need to consider the number of dirty buckets as well
+ * when calculating the proportional_scaled, Otherwise we might
+ * have an unreasonable small writeback rate at a highly fragmented situation
+ * when very few dirty sectors consumed a lot dirty buckets, the
+ * worst case is when dirty buckets reached cutoff_writeback_sync and
+ * dirty data is still not even reached to writeback percent, so the rate
+ * still will be at the minimum value, which will cause the write
+ * stuck at a non-writeback mode.
+ */
+ struct cache_set *c = dc->disk.c;
+
+ int64_t dirty_buckets = c->nbuckets - c->avail_nbuckets;
+
+ if (dc->writeback_consider_fragment &&
+ c->gc_stats.in_use > BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW && dirty > 0) {
+ int64_t fragment =
+ div_s64((dirty_buckets * c->cache->sb.bucket_size), dirty);
+ int64_t fp_term;
+ int64_t fps;
+
+ if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID) {
+ fp_term = dc->writeback_rate_fp_term_low *
+ (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW);
+ } else if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH) {
+ fp_term = dc->writeback_rate_fp_term_mid *
+ (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID);
+ } else {
+ fp_term = dc->writeback_rate_fp_term_high *
+ (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH);
+ }
+ fps = div_s64(dirty, dirty_buckets) * fp_term;
+ if (fragment > 3 && fps > proportional_scaled) {
+ /* Only overrite the p when fragment > 3 */
+ proportional_scaled = fps;
+ }
+ }
+
if ((error < 0 && dc->writeback_rate_integral > 0) ||
(error > 0 && time_before64(local_clock(),
dc->writeback_rate.next + NSEC_PER_MSEC))) {
@@ -977,6 +1015,7 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc)
dc->writeback_metadata = true;
dc->writeback_running = false;
+ dc->writeback_consider_fragment = true;
dc->writeback_percent = 10;
dc->writeback_delay = 30;
atomic_long_set(&dc->writeback_rate.rate, 1024);
@@ -984,6 +1023,9 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc)
dc->writeback_rate_update_seconds = WRITEBACK_RATE_UPDATE_SECS_DEFAULT;
dc->writeback_rate_p_term_inverse = 40;
+ dc->writeback_rate_fp_term_low = 1;
+ dc->writeback_rate_fp_term_mid = 10;
+ dc->writeback_rate_fp_term_high = 1000;
dc->writeback_rate_i_term_inverse = 10000;
WARN_ON(test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags));
diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h
index 3f1230e22de0..02b2f9df73f6 100644
--- a/drivers/md/bcache/writeback.h
+++ b/drivers/md/bcache/writeback.h
@@ -16,6 +16,10 @@
#define BCH_AUTO_GC_DIRTY_THRESHOLD 50
+#define BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW 50
+#define BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID 57
+#define BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH 64
+
#define BCH_DIRTY_INIT_THRD_MAX 64
/*
* 14 (16384ths) is chosen here as something that each backing device