aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlberto Garcia <berto@igalia.com>2015-10-28 17:33:06 +0200
committerKevin Wolf <kwolf@redhat.com>2015-11-12 16:22:46 +0100
commit96e4dedaff9922f87e4ec351d51d3f093198382a (patch)
tree4f13bd41dbde11ddedeb6ce30d0ae0ca11e8ea6e
parent979e9b03fc8c85d3b78a14410c64cbb16d348095 (diff)
block: Add average I/O queue depth to BlockDeviceTimedStats
This patch adds two new fields to BlockDeviceTimedStats that track the average number of pending read and write requests for a block device. The values are calculated for the period of time defined for that interval. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-id: fd31fef53e2714f2f30d59ed58ca2f67ec9ab926.1446044837.git.berto@igalia.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r--block/accounting.c12
-rw-r--r--block/qapi.c5
-rw-r--r--include/block/accounting.h2
-rw-r--r--include/qemu/timed-average.h1
-rw-r--r--qapi/block-core.json9
-rw-r--r--qmp-commands.hx6
-rw-r--r--util/timed-average.c31
7 files changed, 60 insertions, 6 deletions
diff --git a/block/accounting.c b/block/accounting.c
index 61de8ce9bc..a9419315a3 100644
--- a/block/accounting.c
+++ b/block/accounting.c
@@ -143,3 +143,15 @@ int64_t block_acct_idle_time_ns(BlockAcctStats *stats)
{
return qemu_clock_get_ns(clock_type) - stats->last_access_time_ns;
}
+
+double block_acct_queue_depth(BlockAcctTimedStats *stats,
+ enum BlockAcctType type)
+{
+ uint64_t sum, elapsed;
+
+ assert(type < BLOCK_MAX_IOTYPE);
+
+ sum = timed_average_sum(&stats->latency[type], &elapsed);
+
+ return (double) sum / elapsed;
+}
diff --git a/block/qapi.c b/block/qapi.c
index 6169a22243..d20262decb 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -402,6 +402,11 @@ static BlockStats *bdrv_query_stats(const BlockDriverState *bs,
dev_stats->min_flush_latency_ns = timed_average_min(fl);
dev_stats->max_flush_latency_ns = timed_average_max(fl);
dev_stats->avg_flush_latency_ns = timed_average_avg(fl);
+
+ dev_stats->avg_rd_queue_depth =
+ block_acct_queue_depth(ts, BLOCK_ACCT_READ);
+ dev_stats->avg_wr_queue_depth =
+ block_acct_queue_depth(ts, BLOCK_ACCT_WRITE);
}
}
diff --git a/include/block/accounting.h b/include/block/accounting.h
index 1dd582a99a..482926b8ec 100644
--- a/include/block/accounting.h
+++ b/include/block/accounting.h
@@ -78,5 +78,7 @@ void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type);
void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
int num_requests);
int64_t block_acct_idle_time_ns(BlockAcctStats *stats);
+double block_acct_queue_depth(BlockAcctTimedStats *stats,
+ enum BlockAcctType type);
#endif
diff --git a/include/qemu/timed-average.h b/include/qemu/timed-average.h
index f1cdddc48b..364bf88f70 100644
--- a/include/qemu/timed-average.h
+++ b/include/qemu/timed-average.h
@@ -59,5 +59,6 @@ void timed_average_account(TimedAverage *ta, uint64_t value);
uint64_t timed_average_min(TimedAverage *ta);
uint64_t timed_average_avg(TimedAverage *ta);
uint64_t timed_average_max(TimedAverage *ta);
+uint64_t timed_average_sum(TimedAverage *ta, uint64_t *elapsed);
#endif
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 80470da574..6fd68a6d24 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -450,6 +450,12 @@
# @avg_flush_latency_ns: Average latency of flush operations in the
# defined interval, in nanoseconds.
#
+# @avg_rd_queue_depth: Average number of pending read operations
+# in the defined interval.
+#
+# @avg_wr_queue_depth: Average number of pending write operations
+# in the defined interval.
+#
# Since: 2.5
##
@@ -458,7 +464,8 @@
'max_rd_latency_ns': 'int', 'avg_rd_latency_ns': 'int',
'min_wr_latency_ns': 'int', 'max_wr_latency_ns': 'int',
'avg_wr_latency_ns': 'int', 'min_flush_latency_ns': 'int',
- 'max_flush_latency_ns': 'int', 'avg_flush_latency_ns': 'int' } }
+ 'max_flush_latency_ns': 'int', 'avg_flush_latency_ns': 'int',
+ 'avg_rd_queue_depth': 'number', 'avg_wr_queue_depth': 'number' } }
##
# @BlockDeviceStats:
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 3e50f7fbb1..9d8b42f59a 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -2635,6 +2635,12 @@ Each json-object contain the following:
- "avg_flush_latency_ns": average latency of flush operations
in the defined interval, in
nanoseconds (json-int)
+ - "avg_rd_queue_depth": average number of pending read
+ operations in the defined interval
+ (json-number)
+ - "avg_wr_queue_depth": average number of pending write
+ operations in the defined interval
+ (json-number).
- "parent": Contains recursively the statistics of the underlying
protocol (e.g. the host file for a qcow2 image). If there is
no underlying protocol, this field is omitted
diff --git a/util/timed-average.c b/util/timed-average.c
index 98a1170204..a2dfb4834d 100644
--- a/util/timed-average.c
+++ b/util/timed-average.c
@@ -120,8 +120,10 @@ void timed_average_init(TimedAverage *ta, QEMUClockType clock_type,
* expiration time if that's the case.
*
* @ta: the TimedAverage structure
+ * @elapsed: if non-NULL, the elapsed time (in ns) within the current
+ * window will be stored here
*/
-static void check_expirations(TimedAverage *ta)
+static void check_expirations(TimedAverage *ta, uint64_t *elapsed)
{
int64_t now = qemu_clock_get_ns(ta->clock_type);
int i;
@@ -143,6 +145,12 @@ static void check_expirations(TimedAverage *ta)
} else {
ta->current = 1;
}
+
+ /* Calculate the elapsed time within the current window */
+ if (elapsed) {
+ int64_t remaining = ta->windows[ta->current].expiration - now;
+ *elapsed = ta->period - remaining;
+ }
}
/* Account a value
@@ -153,7 +161,7 @@ static void check_expirations(TimedAverage *ta)
void timed_average_account(TimedAverage *ta, uint64_t value)
{
int i;
- check_expirations(ta);
+ check_expirations(ta, NULL);
/* Do the accounting in both windows at the same time */
for (i = 0; i < 2; i++) {
@@ -180,7 +188,7 @@ void timed_average_account(TimedAverage *ta, uint64_t value)
uint64_t timed_average_min(TimedAverage *ta)
{
TimedAverageWindow *w;
- check_expirations(ta);
+ check_expirations(ta, NULL);
w = current_window(ta);
return w->min < UINT64_MAX ? w->min : 0;
}
@@ -193,7 +201,7 @@ uint64_t timed_average_min(TimedAverage *ta)
uint64_t timed_average_avg(TimedAverage *ta)
{
TimedAverageWindow *w;
- check_expirations(ta);
+ check_expirations(ta, NULL);
w = current_window(ta);
return w->count > 0 ? w->sum / w->count : 0;
}
@@ -205,6 +213,19 @@ uint64_t timed_average_avg(TimedAverage *ta)
*/
uint64_t timed_average_max(TimedAverage *ta)
{
- check_expirations(ta);
+ check_expirations(ta, NULL);
return current_window(ta)->max;
}
+
+/* Get the sum of all accounted values
+ * @ta: the TimedAverage structure
+ * @elapsed: if non-NULL, the elapsed time (in ns) will be stored here
+ * @ret: the sum of all accounted values
+ */
+uint64_t timed_average_sum(TimedAverage *ta, uint64_t *elapsed)
+{
+ TimedAverageWindow *w;
+ check_expirations(ta, elapsed);
+ w = current_window(ta);
+ return w->sum;
+}