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README.md

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+chroprof - Profiling for [Chronos](https://github.com/status-im/nim-chronos)
+============================================================================
+
+This repo contains a usable profiler for [Chronos](https://github.com/status-im/nim-chronos). For the time being, it requires a modified version of Chronos ([V3](https://github.com/codex-storage/nim-chronos/tree/feature/profiler), [V4](https://github.com/codex-storage/nim-chronos/tree/feature/profiler-v4)) which has profiling hooks enabled.
+
+1. [Enabling profiling]()
+2. [Looking at metrics]()
+2. [Enabling profiling with Prometheus metrics]()
+3. [Limitations]()
+
+
+## Enabling Profiling
+
+Profiling must be enabled per event loop thread. To enable it, you need to call,
+from the thread that will run your event loop:
+
+```nim
+import chroprof
+
+enableProfiling()
+``` 
+
+## Looking at Metrics
+
+At any time during execution, you can get a snapshot of the profiler metrics 
+by calling `getMetrics()`. This will return a [`MetricsTotals`]() object which
+is a table mapping [`FutureType`]()s to [`AggregateMetrics`](). You may then
+print, log, or do whatever you like with those. 
+
+`getMetrics()` will return the metrics for the event loop that is running 
+(or ran) on the calling thread.
+
+## Enabling profiling with Prometheus metrics
+
+You can export metrics on the top-`k` async procs that are occupying the event
+loop thread the most by enabling the profiler's [nim-metrics]() collector:
+
+```nim
+import chroprof/collector
+
+# Exports metrics for the 50 heaviest procs
+enableProfilerMetrics(50)
+```
+
+with the help of [Grafana](),