Metrics for C++ programs

Fine-grained application metrics and reporting.

• Event counters
• Timers w/ distribution estimates & percentiles
• One, five, fifteen minute rates

Usage, TL;DR edition:

ccmetrics::MetricRegistry registry;

void work() {
    UPDATE_COUNTER("work", registry);

    if (fast_path) {

        //
        // stuff
        //

    } else {
        SCOPED_TIMER("slow", registry);

        //
        // expensive stuff
        //
    }
}

//
// Reporting
//

for (auto& entry : registry.counters()) {
    printf("%s %" PRId64"\n", entry.first.c_str(),
        entry.second->value());
}

for (auto& entry : registry.timers()) {
    printf("%s %" PRId64" %f %f %f\n", entry.first.c_str(),
        entry.second->count(),
        entry.second->oneMinuteRate(),
        entry.second->fiveMinuteRate(),
        entry.second->fifteenMinuteRate());
    if (g_verbose) {
        printf("99th percentile: %f\n", entry.second->snapshot().get99tile());
    }
}

Tip of the hat to Coda Hale / Yammer.

Supported platforms

ccmetrics is known to work on the following platforms / compilers:

• Windows with Visual Studio 2013+ (dynamic linking only)
• Linux with GCC 4.8
• OS X 10.6+ with Xcode 6.2+

It should build with any compiler that supports C++11 language features like auto type specification and std::atomic support. Platforms without a pthreads implementation will likely need to port the TLS implementation in thread_local_detail.h.

License

Copyright © 2015 Nathan Rosenblum flander@gmail.com

Licensed under the MIT License.

References

This library was inspired by the excellent Java metrics library, and owes many of its interfaces to that project.

ccmetrics uses several other open-source libraries:

• RapidJSON for JSON serialization
• cppformat for general formatting
• Google Test for unit tests