Yeah, Pavel is more correct. That functionality was from very beginning and [1] just exposed the options to the public :) Xiaoming, you may try to run SPECjvm2008/DaCapo with this option turned on/off to measure performance impact.
Thanks, Aleksey. On Fri, Dec 19, 2008 at 11:26 AM, Pavel Pervov <[email protected]> wrote: > These options were always available in DRLVM, and [1] only made them > available for configuration from command line. > > Pavel. > > P.S. I can also recall some issues related to changing order of fields > which were introducing measurable preformance loss on various > benchmarks. > > On Fri, Dec 19, 2008 at 11:16 AM, Aleksey Shipilev > <[email protected]> wrote: >> Hi, Xiaoming! >> >> If I recall correctly, field sorting incurs some performance >> degradations on some of SPECjvm2008 benchmarks. But it helps >> SPECjbb2005 a lot, say +1-2%. Here's the issue [1], where these >> options were introduced. >> >> Thanks, >> Aleksey. >> >> [1] https://issues.apache.org/jira/browse/HARMONY-5040 >> >> On Fri, Dec 19, 2008 at 10:25 AM, xiaoming gu <[email protected]> wrote: >>> Hi, all. I'm studying fields' offsets these days. I find there are some >>> ordering operations for instance fields and static fields seperately in >>> assign_offsets_to_fields() in Prepare.cpp. These orderings are according to >>> field size to reduce internal fragmentation. I don't know why such >>> operations are turned off by default. Is there any concern I missed? Thanks. >>> >>> Xiaoming >>> >>> -- >>> I believe that unarmed truth and unconditional love will have the final word >>> in reality. --Martin Luther King Jr. >>> >> >
