Log "request x-rays" for rust programs instrumented with tracing. This includes aggregated wall/own times as frequently found in flame graphs in a human-friendly text format.
To deploy it, you don't need some complicated services, just some local code added to your instrumented program.
This makes answers to these question often trivial to answer:
It looks like this:
``` Dec 20 18:48:32.405 INFO Call summary of request@examples/nested.rs:47
# calls │ ∑ wall ms │ ∑ own ms │ span tree
────────────┼──────────────┼──────────────┼───────────────────────
0 001 ┊ 377.886 ┊ 0.260 ┊ ┬ request
0 001 ┊ 120.704 ┊ 48.896 ┊ ├┬ nested
0 001 ┊ 0.008 ┊ 0.008 ┊ ┊├─ random
1 000 ┊ 64.347 ┊ 64.347 ┊ ┊╰─ repeated
0 002 ┊ 0.118 ┊ 0.118 ┊ ├─ repeated
0 001 ┊ 3.818 ┊ 0.049 ┊ ├┬ nest_deeply
0 001 ┊ 3.762 ┊ 0.053 ┊ ┊╰┬ nest_deeply
0 001 ┊ 3.702 ┊ 0.057 ┊ ┊ ╰┬ nest_deeply
0 001 ┊ 3.637 ┊ 0.056 ┊ ┊ ╰┬ nest_deeply
0 001 ┊ 3.574 ┊ 0.058 ┊ ┊ ╰┬ nest_deeply
0 001 ┊ 3.503 ┊ 0.061 ┊ ┊ ╰┬ nest_deeply
0 001 ┊ 3.435 ┊ 0.063 ┊ ┊ ╰┬ nest_deeply
0 001 ┊ 3.365 ┊ 0.066 ┊ ┊ ╰┬ nest_deeply
0 001 ┊ 3.292 ┊ 3.292 ┊ ┊ ╰─ nest_deeply
0 001 ┊ 252.949 ┊ 49.258 ┊ ╰┬ nested2
0 001 ┊ 0.006 ┊ 0.006 ┊ ├─ random
1 000 ┊ 63.343 ┊ 63.343 ┊ ├─ repeated
0 001 ┊ 132.841 ┊ 54.091 ┊ ╰┬ nested
0 001 ┊ 0.007 ┊ 0.007 ┊ ├─ random
1 000 ┊ 70.875 ┊ 70.875 ┊ ╰─ repeated
```
Let's assume that you already have an explicit setup for tracing like this, then you simply
need to add the highlighted line:
```rust use reqray::CallTreeCollector; use tracing_subscriber::{EnvFilter, util::SubscriberInitExt, fmt, prelude::*};
let fmt_layer = fmt::layer()
.with_target(false);
let filter_layer = EnvFilter::try_from_default_env()
.or_else(|_| EnvFilter::try_new("info"))
.unwrap();
tracing_subscriber::registry()
// -----------------------------------------------
.with(CallTreeCollector::default())
// -----------------------------------------------
.with(filter_layer)
.with(fmt_layer)
.init();
```
Instead of CallTreeCollector::default() you can chose a more explicit config:
```rust // ... let calltreecollector = CallTreeCollectorBuilder::default() .maxcalldepth(10) .buildwithcollector( LoggingCallTreeCollectorBuilder::default() .left_margin(20) .build(), );
tracing_subscriber::registry()
.with(call_tree_collector)
// ...
```
When working together with Klas Kalass, he created something similar for Java: the Fuava CTProfiler.
It proved to be immensely useful at a nearly daily basis. Thank you, Klas!
Since then, I have worked with sophisticated distributed tracing systems, but they often lacked aggregation possibilities. Others hacked some interesting aggregation scripts on top and I myself became somewhat obsessed with creating similar scripts.
I felt very welcome when I suggested something like this in issue tracing#639. Thank you, @hawkw!
Similarly, Eliza was very supportive and helpful in the tracing discod channel. Thank you, Eliza!
Contributions in the form of documentation and bug fixes are highly welcome. Please start a discussion with me before working on larger features.
I'd really appreciate tests for all new features. Please run cargo test
before submitting a pull request. Just use cargo fmt for formatting.
Feature ideas are also welcome -- just know that this is a pure hobby side project and I will not allocate a lot of bandwidth to this. Therefore, important bug fixes are always prioritised.
By submitting a pull request, you agree to license your changes via all the current licenses of the project.