MPS issue job003857

TitleAMC now slower than 1.113
Statusclosed
Priorityoptional
Assigned userDavid Lovemore
OrganizationRavenbrook
DescriptionDuring release testing, we found that gcbench was running slower for AMC than in version 1.113.
AnalysisSee [2] for analysis. In summary the ChainDeferral used to only test generation 0. Generation 1 wouldn't get collected when it was full, but would get collected the next time generation 0 filled up. This meant that generation 1 was effectively larger, but less well regulated.

The fix is to add half generation 0's size to generation 1, and recommend retuning of chain parameters.
How foundmanual_test
Evidence[1] "Benchmark comparison with 1.113" <https://info.ravenbrook.com/mail/2014/06/19/18-51-29/0/>
[2] "Re: Benchmark comparison with 1.113" <https://info.ravenbrook.com/mail/2014/07/04/12-47-20/0/>
Created byDavid Lovemore
Created on2014-07-04 13:44:42
Last modified byDavid Lovemore
Last modified on2014-07-04 13:49:31
History2014-07-04 DL Created

Fixes

Change Effect Date User Description
186824 closed 2014-07-04 13:32:45 David Lovemore Adjust generation sizes for the default chain.
Add release note recommending retuning of generation sizes.