Changing javac default initial heap size

[Wade Hennessey]

Thanks, that's exactly what I was looking for. -wade

On Wed, Oct 11, 2017 at 3:21 AM, Erik Joelsson <erik.joelsson at oracle.com>
wrote:

> Hello,
>
> I believe Wade is rather asking about the resulting javac binary that the
> build produces. If that's the case, you need to edit
> jdk/make/launcher/Launcher-jdk.compiler.gmk and add your desired flags to
> the JAVA_ARGS argument to SetupBuildLauncher for javac. Example:
>
> $(eval $(call SetupBuildLauncher, javac, \
>    MAIN_CLASS := com.sun.tools.javac.Main, \
>    JAVA_ARGS := --add-modules ALL-DEFAULT -Xms512m, \
>    CFLAGS := -DEXPAND_CLASSPATH_WILDCARDS, \
> ))
>
> (I have not tested this, but it should work)
>
> /Erik
>
> On 2017-10-11 01:44, David Holmes wrote:
>
>> Hi Wade,
>>
>> On 11/10/2017 9:01 AM, Wade Hennessey wrote:
>>
>>> The default initial heap size in OpenJDK9 is 8m (-Xms8m), and I'd like to
>>> increase it, but I can't find how this is specified in the build process.
>>> It seams that most/all java binaries are based on the same main.c program
>>> that launches a specific binary such as javac by passing it parameters
>>> through some sort of "Launcher" that specifes the command line options.
>>> Unfortunately  I don't understand how this is specified when javac is
>>> linked.  -wade
>>>
>>
>> javac compilations are mainly controlled through
>>
>> - make/common/SetupJavaCompilers.gmk
>>
>> but also see:
>>
>> - make/common/JavaCompilation.gmk
>> - make/CompileJavaModules.gmk
>>
>> You can either adjust the flags you pass into the calls (from various
>> makefiles) defined in SetupJavaCompilers or you can edit the FLAGS
>> definitions in there directly e.g. to add -J-Xms16m
>>
>> Also look at the definition for JAVA_TOOL_FLAGS_SMALL.
>>
>> PS. The above are for new JDK 10 repo layout. For 9 it is probably in
>> jdk/make.
>>
>> HTH
>>
>> David
>>
>>
>