Re: [PATCH v2 3/4] ceph: include average/stddev r/w/m latency in mds metrics

Xiubo Li <xiubli@xxxxxxxxxx> · Tue, 14 Sep 2021 21:57:02 +0800

On 9/14/21 4:49 PM, Venky Shankar wrote:
The use of `jiffies_to_timespec64()` seems incorrect too, switch
that to `ktime_to_timespec64()`.

I think this has been missed after I switched the jeffies to ktime for 
the r_start and r_end in my previous patch set.

This LGTM :-)

Signed-off-by: Venky Shankar <vshankar@xxxxxxxxxx>
---
  fs/ceph/metric.c | 35 +++++++++++++++++++----------------
  fs/ceph/metric.h | 48 +++++++++++++++++++++++++++++++++---------------
  2 files changed, 52 insertions(+), 31 deletions(-)

diff --git a/fs/ceph/metric.c b/fs/ceph/metric.c
index 6b774b1a88ce..78a50bb7bd0f 100644
--- a/fs/ceph/metric.c
+++ b/fs/ceph/metric.c
@@ -8,6 +8,13 @@
  #include "metric.h"
  #include "mds_client.h"
  
+static void to_ceph_timespec(struct ceph_timespec *ts, ktime_t val)
+{
+	struct timespec64 t = ktime_to_timespec64(val);
+	ts->tv_sec = cpu_to_le32(t.tv_sec);
+	ts->tv_nsec = cpu_to_le32(t.tv_nsec);
+}
+
  static bool ceph_mdsc_send_metrics(struct ceph_mds_client *mdsc,
  				   struct ceph_mds_session *s)
  {
@@ -26,7 +33,6 @@ static bool ceph_mdsc_send_metrics(struct ceph_mds_client *mdsc,
  	u64 nr_caps = atomic64_read(&m->total_caps);
  	u32 header_len = sizeof(struct ceph_metric_header);
  	struct ceph_msg *msg;
-	struct timespec64 ts;
  	s64 sum;
  	s32 items = 0;
  	s32 len;
@@ -59,37 +65,34 @@ static bool ceph_mdsc_send_metrics(struct ceph_mds_client *mdsc,
  	/* encode the read latency metric */
  	read = (struct ceph_metric_read_latency *)(cap + 1);
  	read->header.type = cpu_to_le32(CLIENT_METRIC_TYPE_READ_LATENCY);
-	read->header.ver = 1;
+	read->header.ver = 2;
  	read->header.compat = 1;
  	read->header.data_len = cpu_to_le32(sizeof(*read) - header_len);
-	sum = m->read_latency_sum;
-	jiffies_to_timespec64(sum, &ts);
-	read->lat.tv_sec = cpu_to_le32(ts.tv_sec);
-	read->lat.tv_nsec = cpu_to_le32(ts.tv_nsec);
+	to_ceph_timespec(&read->lat, m->read_latency_sum);
+	to_ceph_timespec(&read->avg, m->avg_read_latency);
+	to_ceph_timespec(&read->stdev, m->read_latency_stdev);
  	items++;
  
  	/* encode the write latency metric */
  	write = (struct ceph_metric_write_latency *)(read + 1);
  	write->header.type = cpu_to_le32(CLIENT_METRIC_TYPE_WRITE_LATENCY);
-	write->header.ver = 1;
+	write->header.ver = 2;
  	write->header.compat = 1;
  	write->header.data_len = cpu_to_le32(sizeof(*write) - header_len);
-	sum = m->write_latency_sum;
-	jiffies_to_timespec64(sum, &ts);
-	write->lat.tv_sec = cpu_to_le32(ts.tv_sec);
-	write->lat.tv_nsec = cpu_to_le32(ts.tv_nsec);
+	to_ceph_timespec(&write->lat, m->write_latency_sum);
+	to_ceph_timespec(&write->avg, m->avg_write_latency);
+	to_ceph_timespec(&write->stdev, m->write_latency_stdev);
  	items++;
  
  	/* encode the metadata latency metric */
  	meta = (struct ceph_metric_metadata_latency *)(write + 1);
  	meta->header.type = cpu_to_le32(CLIENT_METRIC_TYPE_METADATA_LATENCY);
-	meta->header.ver = 1;
+	meta->header.ver = 2;
  	meta->header.compat = 1;
  	meta->header.data_len = cpu_to_le32(sizeof(*meta) - header_len);
-	sum = m->metadata_latency_sum;
-	jiffies_to_timespec64(sum, &ts);
-	meta->lat.tv_sec = cpu_to_le32(ts.tv_sec);
-	meta->lat.tv_nsec = cpu_to_le32(ts.tv_nsec);
+	to_ceph_timespec(&meta->lat, m->metadata_latency_sum);
+	to_ceph_timespec(&meta->avg, m->avg_metadata_latency);
+	to_ceph_timespec(&meta->stdev, m->metadata_latency_stdev);
  	items++;
  
  	/* encode the dentry lease metric */
diff --git a/fs/ceph/metric.h b/fs/ceph/metric.h
index a5da21b8f8ed..2dd506dedebf 100644
--- a/fs/ceph/metric.h
+++ b/fs/ceph/metric.h
@@ -19,27 +19,39 @@ enum ceph_metric_type {
  	CLIENT_METRIC_TYPE_OPENED_INODES,
  	CLIENT_METRIC_TYPE_READ_IO_SIZES,
  	CLIENT_METRIC_TYPE_WRITE_IO_SIZES,
-
-	CLIENT_METRIC_TYPE_MAX = CLIENT_METRIC_TYPE_WRITE_IO_SIZES,
+	CLIENT_METRIC_TYPE_AVG_READ_LATENCY,
+	CLIENT_METRIC_TYPE_STDEV_READ_LATENCY,
+	CLIENT_METRIC_TYPE_AVG_WRITE_LATENCY,
+	CLIENT_METRIC_TYPE_STDEV_WRITE_LATENCY,
+	CLIENT_METRIC_TYPE_AVG_METADATA_LATENCY,
+	CLIENT_METRIC_TYPE_STDEV_METADATA_LATENCY,
+
+	CLIENT_METRIC_TYPE_MAX = CLIENT_METRIC_TYPE_STDEV_METADATA_LATENCY,
  };
  
  /*
   * This will always have the highest metric bit value
   * as the last element of the array.
   */
-#define CEPHFS_METRIC_SPEC_CLIENT_SUPPORTED {	\
-	CLIENT_METRIC_TYPE_CAP_INFO,		\
-	CLIENT_METRIC_TYPE_READ_LATENCY,	\
-	CLIENT_METRIC_TYPE_WRITE_LATENCY,	\
-	CLIENT_METRIC_TYPE_METADATA_LATENCY,	\
-	CLIENT_METRIC_TYPE_DENTRY_LEASE,	\
-	CLIENT_METRIC_TYPE_OPENED_FILES,	\
-	CLIENT_METRIC_TYPE_PINNED_ICAPS,	\
-	CLIENT_METRIC_TYPE_OPENED_INODES,	\
-	CLIENT_METRIC_TYPE_READ_IO_SIZES,	\
-	CLIENT_METRIC_TYPE_WRITE_IO_SIZES,	\
-						\
-	CLIENT_METRIC_TYPE_MAX,			\
+#define CEPHFS_METRIC_SPEC_CLIENT_SUPPORTED {	    \
+	CLIENT_METRIC_TYPE_CAP_INFO,		    \
+	CLIENT_METRIC_TYPE_READ_LATENCY,	    \
+	CLIENT_METRIC_TYPE_WRITE_LATENCY,	    \
+	CLIENT_METRIC_TYPE_METADATA_LATENCY,	    \
+	CLIENT_METRIC_TYPE_DENTRY_LEASE,	    \
+	CLIENT_METRIC_TYPE_OPENED_FILES,	    \
+	CLIENT_METRIC_TYPE_PINNED_ICAPS,	    \
+	CLIENT_METRIC_TYPE_OPENED_INODES,	    \
+	CLIENT_METRIC_TYPE_READ_IO_SIZES,	    \
+	CLIENT_METRIC_TYPE_WRITE_IO_SIZES,	    \
+	CLIENT_METRIC_TYPE_AVG_READ_LATENCY,	    \
+	CLIENT_METRIC_TYPE_STDEV_READ_LATENCY,	    \
+	CLIENT_METRIC_TYPE_AVG_WRITE_LATENCY,	    \
+	CLIENT_METRIC_TYPE_STDEV_WRITE_LATENCY,	    \
+	CLIENT_METRIC_TYPE_AVG_METADATA_LATENCY,    \
+	CLIENT_METRIC_TYPE_STDEV_METADATA_LATENCY,  \
+						    \
+	CLIENT_METRIC_TYPE_MAX,			    \
  }
  
  struct ceph_metric_header {
@@ -61,18 +73,24 @@ struct ceph_metric_cap {
  struct ceph_metric_read_latency {
  	struct ceph_metric_header header;
  	struct ceph_timespec lat;
+	struct ceph_timespec avg;
+	struct ceph_timespec stdev;
  } __packed;
  
  /* metric write latency header */
  struct ceph_metric_write_latency {
  	struct ceph_metric_header header;
  	struct ceph_timespec lat;
+	struct ceph_timespec avg;
+	struct ceph_timespec stdev;
  } __packed;
  
  /* metric metadata latency header */
  struct ceph_metric_metadata_latency {
  	struct ceph_metric_header header;
  	struct ceph_timespec lat;
+	struct ceph_timespec avg;
+	struct ceph_timespec stdev;
  } __packed;
  
  /* metric dentry lease header */







