From: haoyixing <haoyixing@kuaishou.com>
Date: Fri, 25 Mar 2022 03:02:13 +0000 (+0000)
Subject: mds: add a perf counter to record slow replies
X-Git-Tag: v17.2.1~61^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=a957d231bace0143d786ae696ff8dbcd5ee70f52;p=ceph.git

mds: add a perf counter to record slow replies

Though we have MDS_HEALTH_SLOW_METADATA_IO and MDS_HEALTH_SLOW_REQUEST health alert, but those are not
precise nor accumulated. With slow reply counter compared to reply counter, we can find out the ratio
of slow requests through perf dump.

Fixes: https://tracker.ceph.com/issues/55126
Signed-off-by: haoyixing <haoyixing@kuaishou.com>
(cherry picked from commit e8e3b307c87dc9eec2d087b396c0e7a0248b4f1d)
---

diff --git a/src/mds/MDSRank.cc b/src/mds/MDSRank.cc
index 886a379dd7ae..b44870f807a2 100644
--- a/src/mds/MDSRank.cc
+++ b/src/mds/MDSRank.cc
@@ -3346,6 +3346,8 @@ void MDSRank::create_logger()
                             "exi", PerfCountersBuilder::PRIO_INTERESTING);
     mds_plb.add_u64_counter(l_mds_imported_inodes, "imported_inodes", "Imported inodes",
                             "imi", PerfCountersBuilder::PRIO_INTERESTING);
+    mds_plb.add_u64_counter(l_mds_slow_reply, "slow_reply", "Slow replies", "slr",
+                              PerfCountersBuilder::PRIO_INTERESTING);
 
     // caps msg stats
     mds_plb.add_u64_counter(l_mdss_handle_client_caps, "handle_client_caps",
diff --git a/src/mds/MDSRank.h b/src/mds/MDSRank.h
index 784aa5741588..b428f066b976 100644
--- a/src/mds/MDSRank.h
+++ b/src/mds/MDSRank.h
@@ -53,6 +53,7 @@ enum {
   l_mds_request,
   l_mds_reply,
   l_mds_reply_latency,
+  l_mds_slow_reply,
   l_mds_forward,
   l_mds_dir_fetch,
   l_mds_dir_commit,
@@ -704,4 +705,3 @@ public:
 };
 
 #endif // MDS_RANK_H_
-
diff --git a/src/mds/Server.cc b/src/mds/Server.cc
index e6f7e864fb41..80e5cdf72a3e 100644
--- a/src/mds/Server.cc
+++ b/src/mds/Server.cc
@@ -2137,6 +2137,9 @@ void Server::early_reply(MDRequestRef& mdr, CInode *tracei, CDentry *tracedn)
   mds->logger->inc(l_mds_reply);
   utime_t lat = ceph_clock_now() - req->get_recv_stamp();
   mds->logger->tinc(l_mds_reply_latency, lat);
+  if (lat >= g_conf()->mds_op_complaint_time) {
+    mds->logger->inc(l_mds_slow_reply);
+  }
   if (client_inst.name.is_client()) {
     mds->sessionmap.hit_session(mdr->session);
   }
@@ -2195,6 +2198,9 @@ void Server::reply_client_request(MDRequestRef& mdr, const ref_t<MClientReply> &
     mds->logger->inc(l_mds_reply);
     utime_t lat = ceph_clock_now() - mdr->client_request->get_recv_stamp();
     mds->logger->tinc(l_mds_reply_latency, lat);
+    if (lat >= g_conf()->mds_op_complaint_time) {
+      mds->logger->inc(l_mds_slow_reply);
+    }
     if (session && client_inst.name.is_client()) {
       mds->sessionmap.hit_session(session);
     }