Engine::PluginRet Senpai::run()

in src/oomd/plugins/Senpai.cpp [85:141]

• 47 lines of code
• 12 McCabe index (conditional complexity)

Engine::PluginRet Senpai::run(OomdContext& ctx) {
  auto resolved_cgroups = ctx.reverseSort(
      cgroups_,
      [](const CgroupContext& cgroup_ctx) { return cgroup_ctx.id(); });
  // Use reverse iterator after reverseSort to make it normal order
  auto resolvedIt = resolved_cgroups.crbegin();
  auto trackedIt = tracked_cgroups_.begin();

  bool do_aggregate_log = false;
  if (++log_ticks_ >= log_interval_) {
    log_ticks_ = 0;
    do_aggregate_log = true;
  }

  // Iterate both tracked cgroups and resolved cgroups in increasing id order
  while (resolvedIt != resolved_cgroups.crend()) {
    const CgroupContext& cgroup_ctx = *resolvedIt;
    // Use id to identify CgroupContext across intervals, as path, dir_fd, and
    // memory address could all be recycled upon cgroup recreation.
    auto id_opt = cgroup_ctx.id();
    if (!id_opt) {
      continue;
    }
    if (trackedIt == tracked_cgroups_.end() || *id_opt < trackedIt->first) {
      // Resolved cgroup not in tracked map, track it
      // New cgroups will be polled after a "tick" has elapsed
      if (auto new_cgroup_state_opt = initializeCgroup(cgroup_ctx)) {
        tracked_cgroups_.emplace_hint(
            trackedIt, *id_opt, *new_cgroup_state_opt);
      }
      ++resolvedIt;
    } else if (*cgroup_ctx.id() > trackedIt->first) {
      trackedIt = tracked_cgroups_.erase(trackedIt);
    } else {
      bool tick_result = immediate_backoff_
          ? tick_immediate_backoff(cgroup_ctx, trackedIt->second)
          : tick(cgroup_ctx, trackedIt->second);
      if (do_aggregate_log && tick_result) {
        auto& state = trackedIt->second;
        std::ostringstream oss;
        oss << "cgroup " << cgroup_ctx.cgroup().relativePath() << " "
            << state.probe_count << " probe attempts (" << std::setprecision(3)
            << std::fixed << state.probe_bytes / (double)(1 << 30UL) << " gb)";
        OLOG << oss.str();
        // Reset stats
        state.probe_count = 0;
        state.probe_bytes = 0;
      }
      // Keep the tracked cgroups if they are still valid after tick
      trackedIt = tick_result ? std::next(trackedIt)
                              : tracked_cgroups_.erase(trackedIt);
      ++resolvedIt;
    }
  }
  tracked_cgroups_.erase(trackedIt, tracked_cgroups_.end());
  return Engine::PluginRet::CONTINUE;
}