On 12/23/06, Ivan Volosyuk <[EMAIL PROTECTED]> wrote:
On 12/22/06, Weldon Washburn <[EMAIL PROTECTED]> wrote: > On 12/22/06, Mikhail Fursov <[EMAIL PROTECTED]> wrote: > > > > Weldon, > > AFAIR without WBS it's an easy to write a test(we had such tests) that > > will > > work smoothly on SUN or BEA but fails on Harmony. > > Is "run any app RI is able to run" reason enough? > > > Yes indeed this is reason enough for this stage of Harmony VM development. > Taken to the limit, "run any app RI is able to run" means cloning the RI. > At some point in the future we will need to revisit the above rule but its > good nuff for now. BTW, the work balancing system was introduced to workaround missing high priority threads in VM. IMHO, a high priority finalizer thread can do the job.
Very interesting. Please tell me if the following is correct. Without WBS, finalizing objects falls further and further behind because finalization thread(s) are unable to grab enough of the CPU(s) to keep up. Instead of increasing the priority of the finalization thread(s), WBS takes the approach of increasing the number of finalization threads. The net effect is to increase the rate of finalization by diluting the OS ready queue. Does the following alternative design make sense? Assume the OS/VM porting layer allows the VM to change an OS thread's priority appropriately. During VM boot, query the OS to determine the number of CPUs in the box and create one finalizer thread for each CPU. Never create additional finalizer threads. Boost the priority of the finalizer threads above the level of Java app threads (but probably below real time priority.) Note that all of this is orthogonal to "native" vs. "java" finalizer threads. --
Ivan > > On 12/22/06, Weldon Washburn <[EMAIL PROTECTED]> wrote: > > > > > > The existing VM finalizer system has something called a Work Balancing > > > System. It would be good to know the motivation for this feature. If > > > this > > > feature was built for specific workloads, please tell us which ones. > > > Thanks
-- Weldon Washburn Intel Enterprise Solutions Software Division
