console,internal/errors: improve error perf #13743

BridgeAR · 2017-06-17T13:37:51Z

This increases the performance for console.trace and creating a new NodeError by factor 2-3.

Newer v8 versions exclude the constructor from the stack trace
so the recalculation of the trace can be avoided.

Using a object instead of an Error is sufficient for console.trace as the Error
itself won't be used but only the stack trace that would
otherwise be created twice.

Checklist

make -j4 test (UNIX), or vcbuild test (Windows) passes
commit message follows commit guidelines

Affected core subsystem(s)

console, internal/errors

mscdex · 2017-06-17T14:33:52Z

lib/console.js

-  err.message = util.format.apply(null, args);
-  Error.captureStackTrace(err, trace);
-  this.error(err.stack);
+  const o = {


Perhaps we can keep the more descriptive variable name here (err)?

I think it's not really a typical error anymore but I do not have any strong feelings.

TimothyGu

Code changes LGTM. Commit message-wise, I'd prefer if it addresses what is changed rather than what are the results of the changes.

Using a object instead of an Error is sufficient as the Error itself won't be used but only the stack trace that would otherwise be created twice. This improves the overall .trace() performance.

Newer v8 versions exclude the constructor from the stack trace so the recalculation of the trace can be avoided.

BridgeAR · 2017-06-19T16:07:59Z

I changed the commit messages.

jasnell · 2017-06-19T16:55:10Z

lib/internal/errors.js

@@ -28,7 +28,6 @@ function makeNodeError(Base) {
    constructor(key, ...args) {
      super(message(key, args));
      this[kCode] = key;
-      Error.captureStackTrace(this, NodeError);


I'm -1 on removing this line. The fact that NodeError is being used in here should not be visible to the end user. This intentionally removes that frame from the stack trace to provide that transparency.

The frame is not visible because newer v8 versions remove the constructor frame by default.
That's the reason why I removed the Error.captureStackTrace call. Do you maybe know a better description for the commit message to make it clearer?

I checked all other occurrences as well and they are always needed besides here.

oh nice... I knew that change was coming but I wasn't expecting it until 6.x for some reason. :-) ... that's a happy surprise. I withdraw the objection then!

refack · 2017-06-22T18:11:54Z

CI: https://ci.nodejs.org/job/node-test-commit/10734/

refack · 2017-06-22T20:02:25Z

Landed in 70b31ad and 0401754

Using a object instead of an Error is sufficient as the Error itself won't be used but only the stack trace that would otherwise be created twice. This improves the overall .trace() performance. PR-URL: #13743 Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: Timothy Gu <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Michael Dawson <[email protected]> Reviewed-By: Refael Ackermann <[email protected]>

Newer v8 versions exclude the constructor from the stack trace so the recalculation of the trace can be avoided. PR-URL: #13743 Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: Timothy Gu <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Michael Dawson <[email protected]> Reviewed-By: Refael Ackermann <[email protected]>

refack · 2017-06-22T20:03:13Z

Quick sanity of master: https://ci.nodejs.org/job/node-test-commit-linuxone/6833/