Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Update for #449 #455

Merged
merged 1 commit into from
Jan 19, 2016
Merged

Update for #449 #455

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
22 changes: 14 additions & 8 deletions locale/en/docs/guides/simple-profiling.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -131,18 +131,25 @@ of a user request but even in our simple example, time could be lost compiling
regular expressions, generating random salts, generating unique hashes from user
passwords, or inside the Express framework itself.

Since we ran our application using the --prof option, a tick file was generated
Since we ran our application using the `--prof` option, a tick file was generated
in the same directory as your local run of the application. It should have the
form `isolate-0xnnnnnnnnnnnn-v8.log` (where `n` is a digit). In order to make
sense of this file, we need to use the tick processor included in the Node.js
form `isolate-0xnnnnnnnnnnnn-v8.log` (where `n` is a digit).

In order to make sense of this file, we need to use the tick processor included
in the Node.js
source at `<nodejs_dir>/tools/v8-prof/tick-processor.js`. It is important that
the version of the tick-processor comes from the source for the version of node
used to generate the isolate file. (This will no longer be a concern when the
tick processor is [installed by default][].) The raw tick output can be
used to generate the isolate file. The raw tick output can be
processed using this tool by running:

```
node <path_to_nodejs_src>/tools/v8-prof/tick-processor.js isolate-0x101804c00-v8.log >processed.txt
node <path_to_nodejs_src>/tools/v8-prof/tick-processor.js isolate-0xnnnnnnnnnnnn-v8.log > processed.txt
```

Starting in Node.js 5.2.2, the tick processor is bundled with the Node.js binary and can be run using the `--prof-process` flag:

```
node --prof-process isolate-0xnnnnnnnnnnnn-v8.log > processed.txt
```

Opening processed.txt in your favorite text editor will give you a few different
Expand Down Expand Up @@ -174,7 +181,7 @@ taking the most CPU time and see:
```

We see that the top 3 entries account for 72.1% of CPU time taken by the
program.From this output, we immediately see that at least 51.8% of CPU time is
program. From this output, we immediately see that at least 51.8% of CPU time is
taken up by a function called PBKDF2 which corresponds to our hash generation
from a user's password. However, it may not be immediately obvious how the lower
two entries factor into our application (or if it is we will pretend otherwise
Expand Down Expand Up @@ -282,5 +289,4 @@ example, you've seen how the V8 tick processor can help you gain a better
understanding of the performance of your Node.js applications.

[profiler inside V8]: https://developers.google.com/v8/profiler_example
[installed by default]: https://github.com/nodejs/node/pull/3032
[benefits of asynchronous programming]: https://nodesource.com/blog/why-asynchronous