PS actually i think it should scale horizontally a little better than vertically but that's just a guess.
On Tue, Nov 29, 2011 at 10:10 AM, Dmitriy Lyubimov <[email protected]> wrote: > On Tue, Nov 29, 2011 at 9:56 AM, Nathan Halko <[email protected]> > wrote: >> >> The docs look great Dmitriy. Has anyone considered giving oversampling >> ssvd over lanczos which is promising. Trying to scale out horizontally but >> not seeing any difference between using one slave or many slaves. Any >> ideas? (I won't go into detail about the setup here but if sounds familiar >> I'd like to talk more). > > What do you mean by a slave? a mapper? a machine? > > whether you increase input horizontally or vertically, you should see > more mappers. If your cluster has enough capacity to scheudle all > mappers right away, i beleive you will get almost the same time (i.e. > almost linear scaling) for most of the jobs. > >> The basic problem with lanczos in the distributed >> environment seems to be that a matrix-vector multiply is not enough work to >> offset any setup costs, also there is not a distributed orthogonalization >> with lanczos and I'm getting OOM's making it difficult to scale. I would >> still like to contribute what results I have found but I'm short on time so >> nothing besides work directly related to the completion of my thesis will >> happen until that is done. >> > >> On Fri, Nov 25, 2011 at 5:37 PM, Dmitriy Lyubimov <[email protected]> wrote: >> >> > I attached the latex source as well (lyx, actually). I would've used >> > Wiki if it supported mathjax. So anyone can modify the usage if need >> > be. (Anyone who has lyx anyway). >> > >> > Dev docs were attached to several jira issues (and i had blog >> > entries), if you want to move more recent copies of them moved over >> > to wiki, i'd be happy to. Mainly, so far there are 2 working notes, >> > one for original method, and another for power iterations, attached to >> > corresponding jiras. >> > >> > >> > On Fri, Nov 25, 2011 at 4:26 PM, Grant Ingersoll <[email protected]> >> > wrote: >> > > I hooked it into the Algorithms page. >> > > >> > > How do you intend to keep the PDF up to date? I like the focus more on >> > the user, but it would also be good to have some dev docs. >> > > >> > > Also, with both Lanczos and this it would be good if we could hook them >> > into some real examples. >> > > >> > > On Nov 25, 2011, at 5:42 PM, Dmitriy Lyubimov wrote: >> > > >> > >> Hi, >> > >> >> > >> I put a usage and overview doc for SSVD onto wiki. I'd appreciate if >> > >> somebody else could look thru it, to scan for completeness and >> > >> suggestions. >> > >> >> > >> I tried to approach it as a user-facing documentation, i.e. I tried to >> > >> avoid discussing any implementation specifics . >> > >> >> > >> I had several users and Nathan Halko trying it out and actually >> > >> favorably commenting on its scalability vs. Lanczos but i don't know >> > >> first hand of any production use (even our own use is fairly limited >> > >> (in terms of input volume we ever processed) and actually somewhat >> > >> diverged from this Mahout implementation. Perhaps putting it more in >> > >> front of users will help to receive more feedback. >> > >> >> > >> Thanks. >> > >> -Dmitriy >> > > >> > > -------------------------------------------- >> > > Grant Ingersoll >> > > http://www.lucidimagination.com >> > > >> > > >> > > >> > > >> >
