From: Dhairya Parmar <dparmar@redhat.com>
Date: Thu, 2 Mar 2023 13:07:14 +0000 (+0530)
Subject: mds,messages: enable beacon to report clients lagginess
X-Git-Tag: v18.2.4~418^2~7
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=3a2b86236544d4cb9d44e8931c20cd939406e200;p=ceph.git

mds,messages: enable beacon to report clients lagginess
using new MDS health metric

Fixes: https://tracker.ceph.com/issues/58023
Signed-off-by: Dhairya Parmar <dparmar@redhat.com>
(cherry picked from commit 5a0e8a7e703495e958ae7aac79bd9a40d86b19d0)
---

diff --git a/src/mds/Beacon.cc b/src/mds/Beacon.cc
index 35f0f79427d6..4c232707ce32 100644
--- a/src/mds/Beacon.cc
+++ b/src/mds/Beacon.cc
@@ -495,6 +495,24 @@ void Beacon::notify_health(MDSRank const *mds)
     MDSHealthMetric m(MDS_HEALTH_CACHE_OVERSIZED, HEALTH_WARN, css->strv());
     health.metrics.push_back(m);
   }
+
+  // Report laggy client(s) due to laggy OSDs
+  {
+    auto&& laggy_clients = mds->server->get_laggy_clients();
+    if (!laggy_clients.empty()) {
+      std::vector<MDSHealthMetric> laggy_clients_metrics;
+      for (const auto& laggy_client: laggy_clients) {
+        CachedStackStringStream css;
+        *css << "Client " << laggy_client << " is laggy; not evicted"
+            << " because some OSD(s) is/are laggy";
+        MDSHealthMetric m(MDS_HEALTH_CLIENTS_LAGGY, HEALTH_WARN, css->strv());
+        laggy_clients_metrics.emplace_back(std::move(m));
+      }
+      auto&& m = laggy_clients_metrics;
+      health.metrics.insert(std::end(health.metrics), std::cbegin(m),
+                            std::cend(m));
+    }
+  }
 }
 
 MDSMap::DaemonState Beacon::get_want_state() const
diff --git a/src/messages/MMDSBeacon.h b/src/messages/MMDSBeacon.h
index f2fa150bee31..d843b0e76610 100644
--- a/src/messages/MMDSBeacon.h
+++ b/src/messages/MMDSBeacon.h
@@ -45,6 +45,7 @@ enum mds_metric_t {
   MDS_HEALTH_SLOW_REQUEST,
   MDS_HEALTH_CACHE_OVERSIZED,
   MDS_HEALTH_SLOW_METADATA_IO,
+  MDS_HEALTH_CLIENTS_LAGGY,
   MDS_HEALTH_DUMMY, // not a real health warning, for testing
 };
 
@@ -63,6 +64,7 @@ inline const char *mds_metric_name(mds_metric_t m)
   case MDS_HEALTH_SLOW_REQUEST: return "MDS_SLOW_REQUEST";
   case MDS_HEALTH_CACHE_OVERSIZED: return "MDS_CACHE_OVERSIZED";
   case MDS_HEALTH_SLOW_METADATA_IO: return "MDS_SLOW_METADATA_IO";
+  case MDS_HEALTH_CLIENTS_LAGGY: return "MDS_CLIENTS_LAGGY";
   case MDS_HEALTH_DUMMY: return "MDS_DUMMY";
   default:
     return "???";
@@ -97,6 +99,8 @@ inline const char *mds_metric_summary(mds_metric_t m)
     return "%num% MDSs report oversized cache";
   case MDS_HEALTH_SLOW_METADATA_IO:
     return "%num% MDSs report slow metadata IOs";
+  case MDS_HEALTH_CLIENTS_LAGGY:
+    return "%num% client(s) laggy due to laggy OSDs";  
   default:
     return "???";
   }