#pragma once #include #include #if defined(OS_LINUX) struct taskstats; namespace DB { /// Provides several essential per-task metrics by reading data from Procfs (when available). class ProcfsMetricsProvider : private boost::noncopyable { public: explicit ProcfsMetricsProvider(pid_t /*tid*/); ~ProcfsMetricsProvider(); /// Updates only a part of taskstats struct's fields: /// - cpu_run_virtual_total, cpu_delay_total (when /proc/thread-self/schedstat is available) /// - blkio_delay_total (when /proc/thread-self/stat is available) /// - rchar, wchar, read_bytes, write_bytes (when /proc/thread-self/io is available) /// See: man procfs void getTaskStats(::taskstats & out_stats) const; /// Tells whether this metrics (via Procfs) is provided on the current platform static bool isAvailable() noexcept; private: void readParseAndSetThreadCPUStat(::taskstats & out_stats, char *, size_t) const; void readParseAndSetThreadBlkIOStat(::taskstats & out_stats, char *, size_t) const; void readParseAndSetThreadIOStat(::taskstats & out_stats, char *, size_t) const; int thread_schedstat_fd = -1; int thread_stat_fd = -1; int thread_io_fd = -1; /// This field is used for compatibility with TasksStatsCounters::incrementProfileEvents() unsigned short stats_version = 1; /// NOLINT }; } #endif