ok standard 3 days then. On Mon, Mar 7, 2016 at 5:04 PM, ASF GitHub Bot (JIRA) <[email protected]> wrote:
> > [ > https://issues.apache.org/jira/browse/MAHOUT-1640?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15184122#comment-15184122 > ] > > ASF GitHub Bot commented on MAHOUT-1640: > ---------------------------------------- > > Github user smarthi commented on the pull request: > > https://github.com/apache/mahout/pull/81#issuecomment-193536262 > > Seems like it's ASL 2.0 - > https://github.com/vigna/fastutil/blob/master/LICENSE-2.0 > > +1 from me, good to go. > > On Mon, Mar 7, 2016 at 7:21 PM, Dmitriy Lyubimov < > [email protected]> > wrote: > > > @vigna <https://github.com/vigna> is 0.7.2 fastutil is still the > best > > version to use? I can't immediately find the license on it? > > @smarthi <https://github.com/smarthi> et. al. : need a few votes on > > inclusion of fastutil as a dependency > > > > — > > Reply to this email directly or view it on GitHub > > <https://github.com/apache/mahout/pull/81#issuecomment-193522992>. > > > > > > > Better collections would significantly improve vector-operation speed > > --------------------------------------------------------------------- > > > > Key: MAHOUT-1640 > > URL: https://issues.apache.org/jira/browse/MAHOUT-1640 > > Project: Mahout > > Issue Type: Improvement > > Components: collections > > Environment: Darwin lithium.local 14.1.0 Darwin Kernel Version > 14.1.0: Mon Dec 22 23:10:38 PST 2014; root:xnu-2782.10.72~2/RELEASE_X86_64 > x86_64 i386 MacBookPro10,1 Darwin > > java version "1.8.0_31" > > Java(TM) SE Runtime Environment (build 1.8.0_31-b13) > > Java HotSpot(TM) 64-Bit Server VM (build 25.31-b07, mixed mode) > > Reporter: Sebastiano Vigna > > Assignee: Suneel Marthi > > Labels: legacy, math, scala > > Attachments: fastutil.patch, speed-fastutil, speed-std > > > > > > The collections currently used by Mahout to implement sparse vectors are > extremely slow. The proposed patch (localized to RandomAccessSparseVector) > uses fastutil's maps and the speed improvements in vector benchmarks are > very significant. It would be interesting to see whether these improvements > percolate to high-level classes using sparse vectors. > > I had to patch two unit tests (an off-by-one bug and an overfitting bug; > both were exposed by the different order in which key/values were returned > by iterators). > > The included files speed-std and speed-fastutil show the speed > improvement. Some more speed might be gained by using everywhere the > standard java.util.Map.Entry interface instead of Element. > > DISCLAIMER: The "Times" set of tests has been run multiplying two > identical vectors. The standard tests multiply two random vectors, so in > fact they just test the speed of the underlying map remove() method, as > almost all products are zero. This is not very realistic and was heavily > penalizing fastutil's "true deletions". Better tests, with a typical > overlap of nonzero entries, would be even more realistic. > > > > -- > This message was sent by Atlassian JIRA > (v6.3.4#6332) >
