| Title | MVT creation takes "integer percentage" argument |
| Status | closed |
| Priority | nice |
| Assigned user | Richard Brooksby |
| Organization | Ravenbrook |
| Description | When you call mps_pool_create for an MVT or MVFF pool, you have to pass the argument "mps_count_t fragmentation_limit" which is documented to be "a percentage in (0, 100] that can be used to set an upper limit on the space overhead of MVT in case block death times and allocations do not correlate well." It seems like poor design to use an integer percentage for a proportion when a floating-point number could have been used instead. Also, it's inconsistent with mps_gen_param_s, where a double is used for the mps_mortality proportion. |
| Analysis | Replace fragmentation_limit with a double, at least in the interface. I've now fixed this for the new keyword arguments interface, but just by fixing the interface, rather than reworking the pool class code. |
| How found | inspection |
| Evidence | [1] <http://info.ravenbrook.com/project/mps/master/manual/reference/#mps_class_mvt> |
| Observed in | 1.110.0 |
| Created by | Gareth Rees |
| Created on | 2012-10-17 18:08:42 |
| Last modified by | Richard Brooksby |
| Last modified on | 2013-05-16 13:57:19 |
| History | 2012-10-17 GDR created. 2013-05-16 RB explained fix |
| Change | Effect | Date | User | Description |
|---|---|---|---|---|
| 181862 | closed | 2013-05-16 13:54:06 | Richard Brooksby | The fragmentation limit argument to the MVT pool class is now passed as a floating point fraction, not a percentage, in the keyword interface. Imported from Git Author: Richard Brooksby <rb@ravenbrook.com> 1368708846 +0100 Committer: Richard Brooksby <rb@ravenbrook.com> 1368708846 +0100 sha1: fce7a658a291032c734af083a25b95a3e090bc13 |