Locale dependency of JMH, div by 0 in ListStatistics

[Aleksey Shipilev]

(resending, since Erich was accidentally dropped from To: line; one of
these days I have to figure out how to keep people in loop without
subscribing them...)

-Aleksey.

On 12/22/2014 05:17 PM, Aleksey Shipilev wrote:
> Hi Erich,
> 
> On 12/22/2014 03:54 PM, Erich Schubert wrote:
>> I couldn't find a way to report bugs in JIRA (I find navigating the
>> openJDK web pages horrible, too), so I'm posting to the list.
> 
> Yes, thanks. JIRA is open for submissions for OpenJDK authors only,
> sorry about that. I submitted the bug reports on your behalf. I agree
> both are bugs. Let me attend to them.
> 
>> 1. Running JMH in a different locale prevents it from reporting its
>> version number.
>> I'm using the maven version (1.4) which apparently was built with C
>> locale. But SimpleDateFormat defaults to using the system locale, and
>> thus fails to parse the locale-depedant timestamp format that was
>> used.
>>
>> IMHO the cleanest way is to use a non-locale timestamp, such as RFC 3339.
> 
> https://bugs.openjdk.java.net/browse/CODETOOLS-7901226
> 
>> 2. org.openjdk.jmh.util.ListStatistics#getVariance
>>
>> This will yield a division by 0 if getN() == 1. In order to compute
>> variance, you need n > 1.
>> The code is also inconsistent in the sense that it uses getN() in one
>> place, and count in the other.
> 
> https://bugs.openjdk.java.net/browse/CODETOOLS-7901227
> 
> -Aleksey.
> 
>