[MESOS-8964] Avoid performance penalty of Future for Counters and PushGauges.

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Labels: libprocess performance
• Assignee: Unassigned
• Reporter: Benjamin Mahler
• Created: 30/May/18 01:37
• Updated: 18/Jul/18 18:41

Description

Currently, the Metric interface exposes a Future<double> value() of the current metric value. This means that for synchronous metrics, like Counter and PushGauge, there has to be (1) a memory allocation for the Future's shared pointer, as well as (2) continuations set up when the future is ready within process::await.

(2) Could be eliminated without changing the Metric interface by checking to see if value.isReady() and if so extracting the value rather than using process::await.

(1) Could be eliminated by having two types of metrics, e.g. Metric / AsyncMetric. Or by having two methods, e.g. value() / async_value(), along with a bool async() indicator of which one should be called.

Issue Links

• is related to: MESOS-9072 Improve performance of metrics snapshot.