gold for linking

[Ioi Lam]

On 3/26/17 8:43 PM, Claes Redestad wrote:
> +1, at least to make it an optional setting.
>
> Making it heavily multi-threaded by default may be a pessimization when
> we're doing full image builds, cf. how many of the java tools in the
> build is using serial GC and fewer compiler threads to play nice under
> heavy parallelism.
>
> Have you done any assessment on whether this has any effect on static
> footprint and performance on the resulting images?
>
I haven't done any formal measurements. Anecdotally when I ran a class 
loading benchmark it shows no noticeable difference in performance. I 
didn't measure the size of the libjvm.so

Thanks
- Ioi
> /Claes
>
> On 2017-03-26 12:30, Ioi Lam wrote:
>> I just tried adding -fuse-ld=gold to the g++ linker flags, and my
>> libjvm.so link time shrinks from 18 seconds to 6 seconds. And that's
>> with single threaded linking. If I add "-Wl,--threads
>> -Wl,--thread-count,8" it becomes 4 seconds. It doesn't seem to scale
>> after 8 threads.
>>
>> Any plans for adding official (perhaps optional) support for gold in the
>> JDK build system?
>>
>> Thanks
>> - Ioi