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PHP File Manager + Terminal

Server: www.bmcc.cuny.edu
Software: Apache/2.4.62 (Debian)

Current directory: //agents /nodejs /etw/etw_22

Editing: /agents/nodejs/etw/etw_22/notes.txt

# Usage

To start a trace of this and the VS TypeScript language service - later stop it:

```
wpr -start .\ts-wpr-profile.wprp!TypeScript -filemode
wpr -marker "point of interest"
wpr -stop tstrace.etl "example description"
```

Then to open one of:

```
PerfView tstrace.etl
wpa tstrace.etl
```

# TODO

- Try "wpr -start ts-wpr-profile.wprp!TypeScript -start FileIO" and capture to circular buffer with marker
 - Try out WPA again with activities for both providers.
 - How should this handle initialization and multiple instances?
   - Need to use thread-local storage for the activity stack.
 - Instructions for circular logging and capturing after incident.
   - https://docs.microsoft.com/en-us/windows-hardware/test/wpt/logging-mode

# More info
 - https://nodejs.org/dist/latest-v10.x/docs/api/n-api.html
 - https://docs.microsoft.com/en-us/windows/desktop/tracelogging/trace-logging-portal
 - https://docs.microsoft.com/en-us/windows/desktop/tracelogging/tracelogging-c-cpp-tracelogging-examples
 - https://docs.microsoft.com/en-us/windows-hardware/test/wpt/wpr-command-line-options

# Implementation notes

## Removing the CRT problems:

- NAPI_MODULE macro depends on CRT initialization. Expanded and moved to DllMain.
 - Delay loading depends on delayimp.lib, which depends on CRT. Manually imported functions.
 - Some headers required CRT functions in debug builds. Used intrinsics for those functions.
 - Some default compiler options set security features that depend on CRT (e.g. "/GS"). Disabled those.
 - Disabled C++ exceptions and run-time type information.

## State, threading, and instances

ETW is generally a singleton - either the provider is on or off. This would imply global state.
However are the Activity stacks thread specific?
 - Does JS always run on the same OS thread in V8? If so, could use TLS.
   - It would seem to, at least in Node.js, as it runs on the event loop.
 - The issue is when to delete the activity (on Stop for the thread).
 - But could multiple Node.js contexts be interleaving on the same thread?
   - I don't see why not.
   - However, the interleaved operation should still complete full nested start/stop activities within a JS invocation.
 - This basically means that on any thread, the activity stack is still going to fully populat and unwind
   - But other threads may run in parallel and log activies. So still need to use TLS.
   - Can always bail if logging has never been started.