[Feature request]EventSource events for File IO

[noahfalk]

It would be nice if we logged EventSource events when starting/finishing file IO operations so that profilers could understand where execution is IO bound rather than CPU bound. ETW provides events in a windows-specific context but doing it via EventSource would let us collect similar data using EventPipe as a uniform xplat tracing option. I haven't dived into the details of figuring out what the exact events should be or how we'd visualize it. This issue is just to track the idea.

[ghost]

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Issue Details

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It would be nice if we logged EventSource events when starting/finishing file IO operations so that profilers could understand where execution is IO bound rather than CPU bound. ETW provides events in a windows-specific context but doing it via EventSource would let us collect similar data using EventPipe as a uniform xplat tracing option. I haven't dived into the details of figuring out what the exact events should be or how we'd visualize it. This issue is just to track the idea.

Author:	noahfalk
Assignees:	-
Labels:	`enhancement`, `area-System.IO`
Milestone:	-

[adamsitnik]

I am very supportive of this idea. 👍

or how we'd visualize it.

If we are able to connect the event with a CPU sample (by for example using the stack trace), we could extend the current speedscope exporter logic and emit OPEN/CLOSE events for the IO events as if they were just another method on the call stack.

Example:

void M()
{
    File.WriteAllText("test.txt", "test");
}

Currently:

Open M
Open File.WriteAllText
Close File.WriteAllText
Close M

After:

Open M
Open File.WriteAllText
Open FILE_WRITE
Close FILE_WRITE
Close File.WriteAllText
Close M

For Chromium, we could do the same and assign a new category to it, so perhaps it would get different color that typical CPU work.