Commit 70c94820 authored by Xiubo Li's avatar Xiubo Li Committed by Ilya Dryomov
Browse files

ceph: add metadata perf metric support 

Add a new "r_ended" field to struct ceph_mds_request and use that to
maintain the average latency of MDS requests.

URL: https://tracker.ceph.com/issues/43215


Signed-off-by: default avatarXiubo Li <xiubli@redhat.com>
Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent 97e27aaa

fs/ceph/debugfs.c

+10 −0
Original line number Diff line number Diff line
@@ -171,6 +171,16 @@ static int metric_show(struct seq_file *s, void *p) 
	spin_unlock(&m->write_latency_lock);

	CEPH_METRIC_SHOW("write", total, avg, min, max, sq);



	spin_lock(&m->metadata_latency_lock);

	total = m->total_metadatas;

	sum = m->metadata_latency_sum;

	avg = total > 0 ? DIV64_U64_ROUND_CLOSEST(sum, total) : 0;

	min = m->metadata_latency_min;

	max = m->metadata_latency_max;

	sq = m->metadata_latency_sq_sum;

	spin_unlock(&m->metadata_latency_lock);

	CEPH_METRIC_SHOW("metadata", total, avg, min, max, sq);



	seq_printf(s, "\n");

	seq_printf(s, "item          total           miss            hit\n");

	seq_printf(s, "-------------------------------------------------\n");

fs/ceph/mds_client.c

+7 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
#include <linux/seq_file.h>

#include <linux/ratelimit.h>

#include <linux/bits.h>

#include <linux/ktime.h>



#include "super.h"

#include "mds_client.h"
@@ -2201,6 +2202,7 @@ ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode) 
	mutex_init(&req->r_fill_mutex);

	req->r_mdsc = mdsc;

	req->r_started = jiffies;

	req->r_start_latency = ktime_get();

	req->r_resend_mds = -1;

	INIT_LIST_HEAD(&req->r_unsafe_dir_item);

	INIT_LIST_HEAD(&req->r_unsafe_target_item);
@@ -2547,6 +2549,8 @@ static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc, 
static void complete_request(struct ceph_mds_client *mdsc,

			     struct ceph_mds_request *req)

{

	req->r_end_latency = ktime_get();



	if (req->r_callback)

		req->r_callback(mdsc, req);

	complete_all(&req->r_completion);
@@ -3155,6 +3159,9 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg) 


	/* kick calling process */

	complete_request(mdsc, req);



	ceph_update_metadata_latency(&mdsc->metric, req->r_start_latency,

				     req->r_end_latency, err);

out:

	ceph_mdsc_put_request(req);

	return;

fs/ceph/mds_client.h

+3 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
#include <linux/spinlock.h>

#include <linux/refcount.h>

#include <linux/utsname.h>

#include <linux/ktime.h>



#include <linux/ceph/types.h>

#include <linux/ceph/messenger.h>
@@ -299,6 +300,8 @@ struct ceph_mds_request { 


	unsigned long r_timeout;  /* optional.  jiffies, 0 is "wait forever" */

	unsigned long r_started;  /* start time to measure timeout against */

	unsigned long r_start_latency;  /* start time to measure latency */

	unsigned long r_end_latency;    /* finish time to measure latency */

	unsigned long r_request_started; /* start time for mds request only,

					    used to measure lease durations */

fs/ceph/metric.c

+23 −0
Original line number Diff line number Diff line
@@ -44,6 +44,13 @@ int ceph_metric_init(struct ceph_client_metric *m) 
	m->total_writes = 0;

	m->write_latency_sum = 0;



	spin_lock_init(&m->metadata_latency_lock);

	m->metadata_latency_sq_sum = 0;

	m->metadata_latency_min = KTIME_MAX;

	m->metadata_latency_max = 0;

	m->total_metadatas = 0;

	m->metadata_latency_sum = 0;



	return 0;



err_i_caps_mis:
@@ -123,3 +130,19 @@ void ceph_update_write_latency(struct ceph_client_metric *m, 
			 &m->write_latency_sq_sum, lat);

	spin_unlock(&m->write_latency_lock);

}



void ceph_update_metadata_latency(struct ceph_client_metric *m,

				  ktime_t r_start, ktime_t r_end,

				  int rc)

{

	ktime_t lat = ktime_sub(r_end, r_start);



	if (unlikely(rc && rc != -ENOENT))

		return;



	spin_lock(&m->metadata_latency_lock);

	__update_latency(&m->total_metadatas, &m->metadata_latency_sum,

			 &m->metadata_latency_min, &m->metadata_latency_max,

			 &m->metadata_latency_sq_sum, lat);

	spin_unlock(&m->metadata_latency_lock);

}

fs/ceph/metric.h

+10 −0
Original line number Diff line number Diff line
@@ -28,6 +28,13 @@ struct ceph_client_metric { 
	ktime_t write_latency_sq_sum;

	ktime_t write_latency_min;

	ktime_t write_latency_max;



	spinlock_t metadata_latency_lock;

	u64 total_metadatas;

	ktime_t metadata_latency_sum;

	ktime_t metadata_latency_sq_sum;

	ktime_t metadata_latency_min;

	ktime_t metadata_latency_max;

};



extern int ceph_metric_init(struct ceph_client_metric *m);
@@ -49,4 +56,7 @@ extern void ceph_update_read_latency(struct ceph_client_metric *m, 
extern void ceph_update_write_latency(struct ceph_client_metric *m,

				      ktime_t r_start, ktime_t r_end,

				      int rc);

extern void ceph_update_metadata_latency(struct ceph_client_metric *m,

				         ktime_t r_start, ktime_t r_end,

					 int rc);

#endif /* _FS_CEPH_MDS_METRIC_H */