2 Ongoing monitoring

Setup

One of Tufte's most valuable use cases is for monitoring the ongoing performance of production applications, etc.

The pstats objects generated from Tufte's profiled or profile calls are ~losslessly mergeable.

This gives you a lot of flexibility re: integrating Tufte into your running applications.

As one example, suppose you have an HTTP application that you'd like to monitor+optimize for response times:

• Wrap each endpoint with a sampling call to profile. (E.g. with a Ring middleware).
• Your profile handler can accumulate (merge) pstats into a buffer.
• Every n minutes, drain the buffer and log endpoint performance to a db.
• Trigger alarms if any performance info (e.g. 95th percentile response times) are out of spec. The accumulated pstats info will also be helpful in quickly diagnosing a cause.

tufte/add-accumulating-handler! provides one common/convenient way to do this.

See the example project for more info.

Performance

Tufte's designed specifically to support ongoing use in production, and is highly optimized: its overhead is on the order of a couple nanoseconds per wrapping.

If something's remotely worth profiling, Tufte's overhead should be completely insignificant.

Also, keep in mind that Tufte's conditional profiling gives you complete control over if and when you do pay (however little) for profiling.