Delete unavailable metric

package/src/memmon.cpp

@@ -10,6 +10,7 @@
 #include <iostream>
 #include <limits>
 #include <regex>
+#include <set>
 #include <sstream>
 
 #include "utils.h"
@@ -136,3 +137,44 @@ void const memmon::get_unit_info(nlohmann::json& unit_json) {
  prmon::fill_units(unit_json, params);
  return;
 }
+
+// Toggle on fast memmory monitoring
+void const memmon::do_fastmon() {
+ // Fast monitoring reads the data from a special file
+ // This file is called smaps_rollup instead of smaps
+ input_filename = "smaps_rollup";
+
+ // First discover all available metrics by peeking into self smaps_rollup file
+ std::set<std::string> available_metrics;
+ std::stringstream smaps_fname{"/proc/self/smaps_rollup"};
+ std::ifstream smap_stat{smaps_fname.str()};
+ std::string key_str{}, value_str{};
+ while (smap_stat) {
+ smap_stat >> key_str >> value_str;
+ smap_stat.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
+ if (smap_stat) {
+ if (key_str == "Size:") {
+ available_metrics.insert("vmem");
+ } else if (key_str == "Pss:") {
+ available_metrics.insert("pss");
+ } else if (key_str == "Rss:") {
+ available_metrics.insert("rss");
+ } else if (key_str == "Swap:") {
+ available_metrics.insert("swap");
+ }
+ }
+ }
+
+ // Delete unavailable metrics from the monitored stats
+ // In C++17/20 there are more elegant ways to do this
+ for (auto it = mem_stats.cbegin(); it != mem_stats.cend();) {
+ // Delete unavailable metrics
+ if (available_metrics.count(it->first) == 0) {
+ spdlog::warn("Metric " + it->first +
+ " is not available in fast monitoring");
+ it = mem_stats.erase(it);
+ } else {
+ it++;
+ }
+ }
+};

package/src/memmon.h

@@ -53,7 +53,7 @@ class memmon final : public Imonitor, public MessageBase {
  bool const is_valid() { return true; }
 
  // Toggle on fast memmory monitoring
- inline void const do_fastmon() { input_filename = "smaps_rollup"; };
+ void const do_fastmon();
 };
 REGISTER_MONITOR(Imonitor, memmon, "Monitor memory usage")