Description
- Version: v10.1.0
- Platform: Windows 10 x64 (1803)
- Subsystem: v8 profiler
Summary:
With Node 10 on Windows, the v8 log generated via node --prof no longer quotes paths correctly, causing node --prof-process to treat the backslashes in the paths as escape sequences.
This causes a path like:
C:\Users\Ed\src\neutrino-dev\node_modules\webpack\lib\Stats.js
...to be output as:
C:\u0000\rc\u0000erder\node_modulesëck\u0000tats.js
...which doesn't make for the most readable profiles.
In addition, redirecting stdout when using --prof-process without the --preprocess, results in a binary file (whereas if there is no redirection, text is output to the console as expected).
I'm presuming this is a regression between v8 6.2 and 6.6.
STR:
node --prof node_modules\webpack\bin\webpack.js --mode productionnode --prof-process --preprocess isolate-[IDENTIFIER]-v8.log > preprocessed.jsonnode --prof-process isolate-[IDENTIFIER]-v8.log > processed.txt- Repeat steps 1-3 using Node 8.11.2 instead, and compare output from each.
Expected:
Node 10.1.0 produces comparable output to Node 8.x, that correctly lists the filesystem paths for items in the profile.
Actual:
# Step 1 produces... (note difference in quoting)
Node 10.1.0:
v8-version,6,6,346,27,-node.6,0
shared-library,C:\Users\Ed\Desktop\node-v10.1.0-win-x64\node.exe,0x7ff64f880000,0x7ff650f0f000,0
shared-library,C:\WINDOWS\SYSTEM32\ntdll.dll,0x7ff9b1df0000,0x7ff9b1fd1000,0
shared-library,C:\WINDOWS\System32\KERNEL32.DLL,0x7ff9b0da0000,0x7ff9b0e52000,0
...
Node 8.11.2:
v8-version,6,2,414,54,0
shared-library,"C:\Users\Ed\Desktop\node-v8.11.2-win-x64\node.exe",0x7ff6f9ec0000,0x7ff6fb490000,0
shared-library,"C:\WINDOWS\SYSTEM32\ntdll.dll",0x7ff9b1df0000,0x7ff9b1fd1000,0
shared-library,"C:\WINDOWS\System32\KERNEL32.DLL",0x7ff9b0da0000,0x7ff9b0e52000,0
...
# Step 2 produces...
Node 10.1.0:
{
"code": [
{
"name": "C:\u0000\rsktop\node-v10.1.0-win-x64\node.exe",
"type": "SHARED_LIB"
},
{
"name": "C:\u0000WS\u0000M32\ntdll.dll",
"type": "SHARED_LIB"
},
...Node 8.11.2:
{
"code": [
{
"name": "C:\\Users\\Ed\\Desktop\\node-v8.11.2-win-x64\\node.exe",
"type": "SHARED_LIB"
},
{
"name": "C:\\WINDOWS\\SYSTEM32\\ntdll.dll",
"type": "SHARED_LIB"
},
...# Step 3 produces...
Node 10.1.0 (note: the binary output only occurs when redirecting stdout to a file):
5374 6174 6973 7469 6361 6c20 7072 6f66
696c 696e 6720 7265 7375 6c74 2066 726f
6d20 6973 6f6c 6174 652d 3030 3030 3031
3139 3031 3441 3539 4130 2d76 382e 6c6f
...
Node 8.11.2:
Statistical profiling result from isolate-0000027B49039D30-v8.log, (5485 ticks, 82 unaccounted, 0 excluded).
[Shared libraries]:
ticks total nonlib name
2551 46.5% C:\WINDOWS\SYSTEM32\ntdll.dll
1507 27.5% C:\Users\Ed\Desktop\node-v8.11.2-win-x64\node.exe
...