RFR: JDK-8138864 Build with nice to lower UI impact

[Magnus Ihse Bursie]

On 2015-10-05 11:31, Erik Joelsson wrote:
> Looks ok to me, but I suspect someone will be asking for an explicit 
> way of disabling this soon.
I was just about to reply "just use configure NICE=", but then I had to 
go and check that it worked. It didn't. So, here's an updated patch that 
allow you to override a configure located executable (such as nice) with 
an empty value. The changes are in basics.4m.

http://cr.openjdk.java.net/~ihse/JDK-8138864-make-nice-priority/webrev.02

With this additional fix, you can use "configure NICE=" to disable the 
use of nice.

/Magnus

>
> /Erik
>
> On 2015-10-05 11:21, Magnus Ihse Bursie wrote:
>> Since building the OpenJDK is a heavy operation, the build system 
>> tries to make use as of much of the system resources as possible and 
>> reasonable.
>>
>> However, on most machines except extremely high-end, this means that 
>> few resources are available for other processes. On a developer 
>> machine, building means that other work can get laggy and have poor 
>> response times.
>>
>> There is a simple remedy for this! Using "nice" to lower the priority 
>> for the build process, so the build will wait for normal UI 
>> processes. A single "nice" when handling the parallel targets in 
>> Init.gmk is sufficient.
>>
>> A potential problem could be if this affects performance on dedicated 
>> build servers. I have checked this on Oracle's internal build system, 
>> and there were no measurable regressions. This also stands to reason, 
>> since if there would be, the build server would be running other 
>> processes competing with the build. On a correctly setup build 
>> server, this should not be the case. And if such processes existed, 
>> it would be bad anyway.
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8138864
>> WebRev: 
>> http://cr.openjdk.java.net/~ihse/JDK-8138864-make-nice-priority/webrev.01
>>
>> /Magnus
>>
>