RFR: JDK-8188312 Use CDS if present when running the Boot JDK during build

[David Holmes]

Hi Claes,

On 3/10/2017 8:48 PM, Claes Redestad wrote:
> Hi,
> 
> -Xshare:auto silently ignores failures to map the shared archive and 
> should be safe to use. I think you're thinking of -Xshare:on which will 
> fail/abort the VM if mapping fails.

Ah okay.

In that case seems reasonable. But please test thoroughly across all 
platforms in JPRT.

Thanks,
David

> /Claes
> 
> 
> On 2017-10-03 12:28, David Holmes wrote:
>> Hi Magnus,
>>
>> As I just put in the bug report, it isn't quite this simple. You have 
>> to be able to tolerate/recover from failure to map the shared archive.
>>
>> Cheers,
>> David
>>
>> On 3/10/2017 8:24 PM, Magnus Ihse Bursie wrote:
>>> We should use CDS to minimize Java startup time during build. We run 
>>> multiple Java commands, and every second counts.
>>>
>>> On my machine, I get a ~3% build time speedup with this fix.
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8188312
>>> WebRev: 
>>> http://cr.openjdk.java.net/~ihse/JDK-8188312-use-CDS-for-bootjdk/webrev.01 
>>>
>>>
>>> /Magnus
>