Miscellaneous jar improvements

[Andrew John Hughes]

2009/9/10 Andrew Haley <aph at redhat.com>:
> Martin Buchholz wrote:
>> On Thu, Sep 10, 2009 at 09:57, Andrew Haley<aph at redhat.com> wrote:
>>> Martin Buchholz wrote:
>>>> Regarding improving build times:
>>>>
>>>> The jar command that is actually used to build rt.jar is from the
>>>> bootstrap jdk,
>>>> so patching the jdk that you are about to build won't help directly.
>>> Sure, but building JDK on any free software distro uses the immediately
>>> previous JDK.  Therefore, all that means is that the improvement is
>>> delayed by one release cycle.
>>>
>>>> However, there is another patch that will improve build times
>>>> even when using an old boot jdk.
>>>>
>>>> changeset:   1283:ff32c270102a
>>>> user:        martin
>>>> date:        Mon Jun 22 21:07:20 2009 -0700
>>>> summary:     6853806: Prefer (cd $dir && jar) to jar -C for performance reasons
>
> Weird, I can't find that changeset.  Got a URL?
>

changeset:   1341:ff32c270102a
user:        martin
date:        Mon Jun 22 21:07:20 2009 -0700
summary:     6853806: Prefer (cd $dir && jar) to jar -C for performance reasons

http://hg.openjdk.java.net/jdk7/jdk7/jdk/rev/ff32c270102a

Oh the benefits of a useful summary...

>>>> All told, there were at least 3 separate changesets in openjdk7 to
>>>> make building rt.jar faster.
>>> But you put the lot into http://hg.openjdk.java.net/jdk6/jdk6/jdk/rev/b35f1e5075a4,
>>> right?  That's what we have in IcedTea 6.
>>
>> No, I was too lazy to backport 6853806.
>> (Perhaps I determined it was unnecessary?  I don't recall)
>>
>> The changes to the jar command benefit all users of the jar command,
>> unlike 6853806, which only benefits us poor folks building openjdk.
>
> Aha!  Proof, if any more were needed, that it would be better to have
> had the backport discussion online... ;-)
>
> Out of interest, why does changing "jar -C" to (cd $dir && jar) make
> anything go faster?
>
> Andrew.
>
>
>



-- 
Andrew :-)

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