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 [email protected]

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