Nashorn performance regression from JDK8u5 to JDK8u25?

Bernard Liang bliang at
Tue Nov 25 19:28:35 UTC 2014


Sure, I¹ve reproduced the data you requested below, as they are small
enough to fit comfortably in a standard message. However, in addition I
would still like to reiterate the questions from my previous reply,
regarding across-build Nashorn-related changes and performance benchmarks.

Your reply also suggests that you have some familiarity with Dust, but if
that is not the case, I can certainly provide some more details.

Bernard Liang

===== begin =====
    <li>{title} {name}</li>{~n}

===== end =====
===== begin basic.json =====
  "page_title": "Benchmark",
  "title": "Sir",
  "names": [{
    "name": "Moe"
    "name": "Larry"
    "name": "Curly"
===== end basic.json =====

On 11/25/14, 2:30 AM, "Hannes Wallnoefer" <hannes.wallnoefer at>

>Hi Bernard,
>I'm trying to reproduce your problems. In your first mail to the list
>you wrote you attached a Dust template and JSON data. I think you either
>forgot to attach it, or it was stripped by the list software. Can you
>please try to send it again, or put it somewhere we can download it?
>Am 2014-11-18 um 03:21 schrieb Bernard Liang:
>> Michel et al,
>> I¹ve run our local test battery using the link you provided, and while
>>in some cases there is improvement, overall the performance still seems
>>to be closer to u25 levels than u5 levels. For what it¹s worth, I did
>>notice that the performance improvements from u25 to u40 were generally
>>better in pooled environments than ones where a single instance of the
>>execution environment was running per thread. This leads itself to a few
>>questions, some of which are reiterated from the original inquiry:
>>    *   Is anyone familiar with (significant) specific changes in the
>>Nashorn libraries from u5 => u25 => u40 that might be related to this
>>regression and could explain the u25 and/or u40 changes in more detail
>>(that might have led to the recommendation to use u40)?
>>    *   Do you have any performance suites (internal or other) that test
>>various Nashorn benchmarks across different releases (of JDK8, for
>>instance)? Do the results of those correlate with our findings?
>> Regards,
>> Bernard Liang
>> PS. The output of `java -version` most recently tested was as follows:
>> java version "1.8.0_40-ea"
>> Java(TM) SE Runtime Environment (build 1.8.0_40-ea-b12)
>> Java HotSpot(TM) 64-Bit Server VM (build 25.40-b16, mixed mode)
>> Previous versions tested:
>> 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)
>> java version "1.8.0_05"
>> Java(TM) SE Runtime Environment (build 1.8.0_05-b13)
>> Java HotSpot(TM) 64-Bit Server VM (build 25.5-b02, mixed mode)
>> From: Michel Trudeau
>><michel.trudeau at<mailto:michel.trudeau at>>
>> Date: Monday, November 17, 2014 at 1:12 PM
>> To: Bernard Liang <bliang at<mailto:bliang at>>
>> Cc: "nashorn-dev at<mailto:nashorn-dev at>"
>><nashorn-dev at<mailto:nashorn-dev at>>
>> Subject: Re: Nashorn performance regression from JDK8u5 to JDK8u25?
>> Bernard,
>> It'd be great if you could try the latest 8u40 stable build.   We are
>>planning to release 8u40 early in the new year.
>> We also have an optional optimizer in 8u40, enable it with the command
>>line argument '-ot'.
>> Thanks,
>> Michel
>> Bernard Liang wrote:
>> Hello,
>> After running some performance tests on the Cartesian product of
>>([JDK8u5, JDK8u25] x [simple template, complex templates] x
>>[all-or-nothing, streaming chunks] x [single dust instance per thread,
>>pooled dust instances] x [blank Dust instances, Dust instances with
>>templates preloaded]), we find that JDK8u25 performance is very
>>consistently considerably worse than JDK8u5 (by roughly 10-100%, with
>>the average falling somewhere between there). The relevant code has been
>>executed enough times (on the order of 10,000 times) to reach reasonably
>>warmed-up states. If some of the items on the axes of the Cartesian
>>product don¹t make much sense, you can ignore the fuzzy parts of the
>>detailed breakdown for now, with the general understanding that various
>>different environments have been tested and shown to yield the same
>> Some additional high-level context:
>> Dust is basically a templating language used to render JSON data into
>>HTML with compilable ³templates": (we
>>are at the v2.4.2 tag)
>> ³simple template² = ~150 bytes each of one (precompiled) template +
>>context JSON (attached)
>> ³complex templates² = ~350 compiled templates spanning ~245KB in
>>compiled JS + ~75KB of JSON context (proprietary data)
>> >From 
>>, it
>>sounded like there were some recent updates made to Nashorn performance
>>around the u20 mark, but that seems to have caused a regression rather
>>than an improvement. Is this something that nashorn-dev is aware of? Is
>>there any way we can help diagnose the issue further using publicly safe
>>data? (If you¹re looking for a way to reproduce this, the attached basic
>>Dust template + JSON context should be adequate under almost any
>> Regards,
>> Bernard Liang

More information about the nashorn-dev mailing list