Hi mahout. Im finding that in 0.8, my ALS recommender goes extremely slow, but it goes very fast in 0.9 .
- At the time the jobs slows down, there is virtually no disk io. - The CPU cycles fluctuate up and down during this time, but they arent at 100% the whole time. - Mapper percentages increatse by about 2% every hour. So its essentially a hanging job (i.e. the input data set is super small, and the exact same command finishes in about 2 minutes when using mahout 0.9). To look into it, - I saw that, between these two releases, there is a improvement thats been made: https://issues.apache.org/jira/browse/MAHOUT-1264, But there is no associated patch. - Doing a quick git diff, its clear that the VectorSumCombiner seems to have been removed (probably so that mahout could a utility class vector combiner). Im wondering : Has anyone ever seen the 0.8 ALS Recommender job progress *very* slowly, so slowly, that its essentially hanging? Like i said, this bug appears gone in 0.9. Any thoughts would be appreciated. thanks! -- jay vyas
