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apache · Aug 19, 2024 · 09f2f8b · 09f2f8b
1 parent 5fbacbd
commit 09f2f8b
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Showing 3 changed files with 23 additions and 4 deletions.
diff --git a/src/shell/command_helper.h b/src/shell/command_helper.h
@@ -709,6 +709,8 @@ inline std::vector<dsn::http_result> get_metrics(const std::vector<node_desc> &n
     return results;
 }
 
+// Adapt the result returned by `get_metrics` into the structure that could be processed by
+// `remote_command`.
 template <typename... Args>
 inline std::pair<bool, std::string> process_get_metrics_result(const dsn::http_result &result,
                                                                const node_desc &node,
@@ -745,6 +747,8 @@ inline std::pair<bool, std::string> process_get_metrics_result(const dsn::http_r
         }                                                                                          \
     } while (0)
 
+// Adapt the result of some parsing operations on the metrics returned by `get_metrics` into the
+// structure that could be processed by `remote_command`.
 template <typename... Args>
 inline std::pair<bool, std::string> process_parse_metrics_result(const dsn::error_s &result,
                                                                  const node_desc &node,
@@ -887,7 +891,7 @@ class aggregate_stats_calcs
         }                                                                                          \
     } while (0)
 
-    // Perform the chosen accum aggregations on the fetched metrics.
+    // Perform the chosen aggregations (both assignment and accum) on the fetched metrics.
     dsn::error_s aggregate_metrics(const std::string &json_string)
     {
         DESERIALIZE_METRIC_QUERY_BRIEF_SNAPSHOT(value, json_string, query_snapshot);
@@ -903,7 +907,7 @@ class aggregate_stats_calcs
         return dsn::error_s::ok();
     }
 
-    // Perform all of the chosen aggregations (both accum and delta) on the fetched metrics.
+    // Perform the chosen aggregations (assignement, accum, delta and rate) on the fetched metrics.
     dsn::error_s aggregate_metrics(const std::string &json_string_start,
                                    const std::string &json_string_end)
     {

diff --git a/src/shell/commands/node_management.cpp b/src/shell/commands/node_management.cpp
@@ -267,6 +267,7 @@ aggregate_meta_server_stats(const node_desc &node,
     auto command_result = process_parse_metrics_result(
         calcs.aggregate_metrics(query_snapshot), node, "aggregate meta server stats");
     if (!command_result.first) {
+        // Metrics failed to be aggregated.
         return command_result;
     }
 
@@ -276,8 +277,10 @@ aggregate_meta_server_stats(const node_desc &node,
 
 struct replica_server_stats
 {
-    double virt_mem_mb;
-    double res_mem_mb;
+    replica_server_stats() = default;
+
+    double virt_mem_mb{0.0};
+    double res_mem_mb{0.0};
 
     DEFINE_JSON_SERIALIZATION(virt_mem_mb, res_mem_mb)
 };
@@ -299,6 +302,7 @@ aggregate_replica_server_stats(const node_desc &node,
         node,
         "aggregate replica server stats");
     if (!command_result.first) {
+        // Metrics failed to be aggregated.
         return command_result;
     }
 
@@ -309,6 +313,7 @@ aggregate_replica_server_stats(const node_desc &node,
 std::vector<std::pair<bool, std::string>> get_server_stats(const std::vector<node_desc> &nodes,
                                                            uint32_t sample_interval_ms)
 {
+    // Ask target node (meta or replica server) for the metrics of server stats.
     const auto &query_string = server_stat_filters().to_query_string();
     const auto &results_start = get_metrics(nodes, query_string);
     std::this_thread::sleep_for(std::chrono::milliseconds(sample_interval_ms));
@@ -330,6 +335,7 @@ std::vector<std::pair<bool, std::string>> get_server_stats(const std::vector<nod
         SKIP_IF_PROCESS_RESULT_FALSE()                                                             \
     }
 
+        // Skip the metrics that failed to be fetched.
         PROCESS_GET_METRICS_RESULT(results_start[i], "starting server stats")
         PROCESS_GET_METRICS_RESULT(results_end[i], "ending server stats")
 
@@ -338,6 +344,7 @@ std::vector<std::pair<bool, std::string>> get_server_stats(const std::vector<nod
         dsn::metric_query_brief_value_snapshot query_snapshot_start;
         dsn::metric_query_brief_value_snapshot query_snapshot_end;
         {
+            // Skip the metrics that failed to be deserialized.
             auto command_result = process_parse_metrics_result(
                 deserialize_metric_query_2_samples(results_start[i].body(),
                                                    results_end[i].body(),

diff --git a/src/utils/metrics.h b/src/utils/metrics.h
@@ -1701,6 +1701,7 @@ DEF_ALL_METRIC_BRIEF_SNAPSHOTS(value);
 
 DEF_ALL_METRIC_BRIEF_SNAPSHOTS(p99);
 
+// Deserialize the json string into the snapshot.
 template <typename TMetricSnapshot>
 inline error_s deserialize_metric_snapshot(const std::string &json_string,
                                            TMetricSnapshot &snapshot)
@@ -1721,10 +1722,13 @@ inline error_s deserialize_metric_snapshot(const std::string &json_string,
         }                                                                                          \
     } while (0)
 
+// Deserialize the json string into the snapshot specially for metric query which is declared
+// internally.
 #define DESERIALIZE_METRIC_QUERY_BRIEF_SNAPSHOT(field, json_string, query_snapshot)                \
     dsn::metric_query_brief_##field##_snapshot query_snapshot;                                     \
     DESERIALIZE_METRIC_SNAPSHOT(json_string, query_snapshot)
 
+// Deserialize both json string samples into respective snapshots.
 template <typename TMetricSnapshot>
 inline error_s deserialize_metric_2_samples(const std::string &json_string_start,
                                             const std::string &json_string_end,
@@ -1736,6 +1740,7 @@ inline error_s deserialize_metric_2_samples(const std::string &json_string_start
     return error_s::ok();
 }
 
+// Deserialize both json string samples into respective snapshots specially for metric queries.
 template <typename TMetricQuerySnapshot>
 inline error_s deserialize_metric_query_2_samples(const std::string &json_string_start,
                                                   const std::string &json_string_end,
@@ -1759,6 +1764,9 @@ inline error_s deserialize_metric_query_2_samples(const std::string &json_string
     return error_s::ok();
 }
 
+// Deserialize both json string samples into respective snapshots specially for metric queries
+// which are declared internally.
+//
 // Currently only Gauge and Counter are considered to have "increase" and "rate", which means
 // samples are needed. Thus brief `value` field is enough.
 #define DESERIALIZE_METRIC_QUERY_BRIEF_2_SAMPLES(                                                  \