RFR: 8175561: Memory churn in jimage code affects startup after resource encapsulation changes

[James Laskey]

+1

Sent from my iPhone

> On Feb 23, 2017, at 6:57 PM, Claes Redestad <claes.redestad at oracle.com> wrote:
> 
> Hi,
> 
> various resource encapsulation changes in 9+148 meant an uptick in
> footprint and startup times for certain applications.
> 
> While some of this regression is hard to avoid[1] (opening readers,
> touching more memory mapped pages etc), a large part is due to simple
> java allocation churn, some of which can be optimized away by reducing
> the number of objects we create when scanning modules for resources.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8175561
> Webrev: http://cr.openjdk.java.net/~redestad/8175561/jdk.01/
> 
> Thanks!
> 
> /Claes
> 
> [1] Things we could do in the future to improve further include adding
> an index to the jimage (too late for 9) or marking modules with no non-encapsulated resources as such so that they can be skipped.