UglifyJS performance

[Marcus Lagergren]

This produces a recording that shows where individual method time is spent (among other things). It can be inspected with the jmc tool in $JAVA_HOME/bin. 
I did multiple runs with the same hot code, and I still have a slowdown. Some things stick out, such as manual calling of accessors, instead of compiling them to method handles ones and for all. We’ll dig further. 

Do you have any idea if you do a lot of JSON stuff in there?

/M

> On 15 Dec 2014, at 15:09, Austin Jackson <themacphage at gmail.com> wrote:
> 
> Chisel runs timing inside itself via calculating the difference of system time before and after, however it may not be as useful as the JVM arguments you just showed me. :)
> 
> 
> ------------
> 
> Austin Jackson 
> themacphage at gmail.com <mailto:themacphage at gmail.com>
> 
> On Dec 15, 2014, at 7:36 AM, Marcus Lagergren <marcus.lagergren at oracle.com <mailto:marcus.lagergren at oracle.com>> wrote:
> 
>> Hi Austin!
>> 
>> Is this particular timing when you are uglifying the jquery test script that you supplied? I do a full Nashorn run, and I indeed see a slowdown that probably shouldn’t be there. There are several sources of overhead and no _huge_ single low hanging fruit, as far as I can tell (damn).
>> 
>> To figure this out, I did a run to produce a Mission Control recording and inspected it.
>> 
>> java -XX:+UnlockCommercialFeatures -XX:+FlightRecorder -XX:FlightRecorderOptions=defaultrecording=true,disk=true,dumponexit=true,dumponexitpath=recording.jfr,stackdepth=1024 - -jar chisel.jar compile uglify -i test-files/jquery-2.1.1.js -o output.js
>> 
>> There is field guard overhead, and there are a few megamorphic fields, but none of this take up more than 15% of the runtime. 
>> 
>> I’ll file this a bug and have someone dive deeper.
>> 
>> Thanks a lot for the report! Much appreciated.
>> 
>> /M
>> 
>>> On 15 Dec 2014, at 04:15, Austin Jackson <themacphage at gmail.com <mailto:themacphage at gmail.com>> wrote:
>>> 
>>> Hello! I’m Austin and I like Nashorn.
>>> 
>>> I was prompted by @lagergren <https://twitter.com/lagergren/status/543526837293711360 <https://twitter.com/lagergren/status/543526837293711360>> to share something with you all that might be of use. I love the work that you all have done with Nashorn making it easy to write JavaScript code and utilize standard Java classes — it’s absolutely great!
>>> 
>>> I, personally, have been using Nashorn to try and run NodeJS modules under it, particularly UglifyJS2.
>>> 
>>> All the files I mention following this are available in a Github release below of my app I’m hoping to use Nashorn with. There is a executable Jar file with the correct directories and instructions on how to run on the website below. The source code is available here below, also.
>>> 
>>> My app is currently a test that wraps UglifyJS2 with bindings in net.austin.chisel.wrappers.UglifyWrapper.java. You can ignore the LESS stuff because that runs on Rhino and isn’t my library (it’s here <https://github.com/marceloverdijk/lesscss-java <https://github.com/marceloverdijk/lesscss-java>>).
>>> 
>>> The important thing is that when I run UglifyJS2 natively under NodeJS (V8), then the compile time is around 1 second more or less (I had no way to time it, that I knew of), but when I run my wrapper, it takes around 47.5 seconds to do the same! However, the resulting copies are verbatim and Nashorn functioned entirely correct, just a big performance problem. @lagergren <https://twitter.com/lagergren/status/544231448900034561 <https://twitter.com/lagergren/status/544231448900034561>> said this might be a warm-up issue.
>>> 
>>> For clarity, I’m running what I believe to be the newest public release of the JDK/JRE. I’m on OS X Yosemite. When I run java -version I get this:
>>> 
>>> java version "1.8.0_25"
>>> Java(TM) SE Runtime Environment (build 1.8.0_25-b17)
>>> Java HotSpot(TM) 64-Bit Server VM (build 25.25-b02, mixed mode)
>>> 
>>> Github release: https://github.com/MacPhage/chisel/releases/tag/v0.0.1 <https://github.com/MacPhage/chisel/releases/tag/v0.0.1> <https://github.com/MacPhage/chisel <https://github.com/MacPhage/chisel>>
>>> Binaries (direct ZIP): chisel-0.0.1-bundle.zip <https://github.com/MacPhage/chisel/releases/download/v0.0.1/chisel-0.0.1-bundle.zip <https://github.com/MacPhage/chisel/releases/download/v0.0.1/chisel-0.0.1-bundle.zip>>
>>> Source code (direct ZIP): Source code (zip) <https://github.com/MacPhage/chisel/archive/v0.0.1.zip <https://github.com/MacPhage/chisel/archive/v0.0.1.zip>>
>>> Github source code at specified commit: https://github.com/MacPhage/chisel/tree/e81ddee8e339d3717beda1ed8a675568be245c22 <https://github.com/MacPhage/chisel/tree/e81ddee8e339d3717beda1ed8a675568be245c22> <https://github.com/MacPhage/chisel/tree/e81ddee8e339d3717beda1ed8a675568be245c22 <https://github.com/MacPhage/chisel/tree/e81ddee8e339d3717beda1ed8a675568be245c22>> 
>>> 
>>> 
>>> If you have any more questions regarding my setup, please tweet me @au5ton <https://twitter.com/au5ton <https://twitter.com/au5ton>> or email themacphage at gmail.com <mailto:themacphage at gmail.com> .
>>> 
>>> 
>>> ------------
>>> 
>>> Austin Jackson 
>>> themacphage at gmail.com <mailto:themacphage at gmail.com> <mailto:themacphage at gmail.com <mailto:themacphage at gmail.com>>
>>