This simple patch doubles the compile-speed of the hotspot repo on Windows

[Fredrik Öhrström]

Issue filed, on its way in:
http://cr.openjdk.java.net/~ohrstrom/webrev-8007446-add-MP/

//Fredrik

2013/2/2 Kelly O'Hair <kelly.ohair at oracle.com>:
> Great stuff.  Have you filed an issue on this? Or shall I?
>
>
> -kto
>
> On Feb 1, 2013, at 4:58 AM, Fredrik Öhrström wrote:
>
>> ie. use /MP on the cl.exe command line.
>>
>> On the build machine (Windows Server 2007, Visual Studio 2010, 32 HT
>> cores, 64GB ram) configuring with:
>>
>> sh configure --enable-sjavac
>> --with-freetype=/cygdrive/d/tools/freetype-amd64
>> --with-boot-jdk=/cygdrive/d/java/jdk-7-fcs-bin-b147/
>>
>> (You need to patch
>> src/share/classes/com/sun/tools/sjavac/server/CompilerThread.java
>> line 256, change equals("windows)" to startswith("windows), this fix
>> is going into tl soon.)
>>
>> Without MP
>> ----- Build times -------
>> Start 2013-02-01 12:23:50
>> End   2013-02-01 12:35:20
>> 00:00:32 corba
>> 00:04:43 hotspot
>> 00:00:15 jaxp
>> 00:00:24 jaxws
>> 00:04:49 jdk
>> 00:00:46 langtools
>> 00:11:30 TOTAL
>> -------------------------
>>
>> With MP
>> ----- Build times -------
>> Start 2013-02-01 12:54:54
>> End   2013-02-01 13:03:56
>> 00:00:31 corba
>> 00:02:20 hotspot
>> 00:00:14 jaxp
>> 00:00:22 jaxws
>> 00:04:44 jdk
>> 00:00:46 langtools
>> 00:09:02 TOTAL
>> -------------------------
>>
>> For such a simple patch it is a nice speedup. Please test and see if
>> it improves the speed on your multi core machines.
>>
>> //Fredrik
>>
>> Oh, and for reference this is the speed without sjavac but with /MP.
>>
>> ----- Build times -------
>> Start 2013-02-01 13:39:38
>> End   2013-02-01 13:51:46
>> 00:00:35 corba
>> 00:02:24 hotspot
>> 00:00:28 jaxp
>> 00:00:36 jaxws
>> 00:07:11 jdk
>> 00:00:48 langtools
>> 00:12:08 TOTAL
>> -------------------------
>>
>> $ hg diff
>> diff -r 67498c863813 make/windows/makefiles/compile.make
>> --- a/make/windows/makefiles/compile.make       Thu Jan 17 12:16:06 2013 +0100
>> +++ b/make/windows/makefiles/compile.make       Fri Feb 01 13:05:08 2013 +0100
>> @@ -44,6 +44,7 @@
>> #   /GS       Inserts security stack checks in some functions (VS2005 default)
>> #   /Oi       Use intrinsics (in /O2)
>> #   /Od       Disable all optimizations
>> +#   /MP       Use multiple cores for compilation
>> #
>> # NOTE: Normally following any of the above with a '-' will turn off that flag
>> #
>> @@ -52,7 +53,7 @@
>> # improving the quality of crash log stack traces involving jvm.dll.
>>
>> # These are always used in all compiles
>> -CXX_FLAGS=/nologo /W3 /WX
>> +CXX_FLAGS=/nologo /W3 /WX /MP
>>
>> # Let's add debug information when Full Debug Symbols is enabled
>> !if "$(ENABLE_FULL_DEBUG_SYMBOLS)" == "1"
>> diff -r 67498c863813 make/windows/makefiles/sa.make
>> --- a/make/windows/makefiles/sa.make    Thu Jan 17 12:16:06 2013 +0100
>> +++ b/make/windows/makefiles/sa.make    Fri Feb 01 13:05:08 2013 +0100
>> @@ -108,6 +108,8 @@
>> SA_LFLAGS = $(SA_LFLAGS) -map -debug
>> !endif
>>
>> +SA_CFLAGS = $(SA_CFLAGS) -MP
>> +
>> # Note that we do not keep sawindbj.obj around as it would then
>> # get included in the dumpbin command in build_vm_def.sh
>