Dmitriy, That sounds great. I eagerly await the patch. Thanks Esh On Aug 13, 2011, at 1:37 PM, Dmitriy Lyubimov wrote:
> Ok, i got u0 working. > > The problem is of course that something called BBt job is to be coerced to > have 1 reducer (it's fine, every mapper won't yeld more than > upper-triangular matrix of k+p x k+p geometry, so even if you end up having > thousands of them, reducer would sum them up just fine. > > it worked before apparently because configuration hold 1 reducer by default > if not set explicitly, i am not quite sure if that's something in hadoop mr > client or mahout change that now precludes it from working. > > anyway, i got a patch (really a one-liner) and an example equivalent to > yours worked fine for me with 3 reducers. > > Also, in the tests, it also requests 3 reducers, but the reason it works in > tests and not in distributed mapred is because local mapred doesn't support > multiple reducers. I investigated this issue before and apparently there > were a couple of patches floating around but for some reason those changes > did not take hold in cdh3u0. > > I will publish patch in a jira shortly and will commit it Sunday-ish. > > Thanks. > -d > > > On Fri, Aug 5, 2011 at 7:06 PM, Eshwaran Vijaya Kumar < > [email protected]> wrote: > >> OK. So to add more info to this, I tried setting the number of reducers to >> 1 and now I don't get that particular error. The singular values and left >> and right singular vectors appear to be correct though (verified using >> Matlab). >> >> On Aug 5, 2011, at 1:55 PM, Eshwaran Vijaya Kumar wrote: >> >>> All, >>> I am trying to test Stochastic SVD and am facing some errors where it >> would be great if someone could clarifying what is going on. I am trying to >> feed the solver a DistributedRowMatrix with the exact same parameters that >> the test in LocalSSVDSolverSparseSequentialTest uses, i.e, Generate a 1000 >> X 100 DRM with SequentialSparseVectors and then ask for blockHeight 251, p >> (oversampling) = 60, k (rank) = 40. I get the following error: >>> >>> Exception in thread "main" java.io.IOException: Unexpected overrun in >> upper triangular matrix files >>> at >> org.apache.mahout.math.hadoop.stochasticsvd.SSVDSolver.loadUpperTriangularMatrix(SSVDSolver.java:471) >>> at >> org.apache.mahout.math.hadoop.stochasticsvd.SSVDSolver.run(SSVDSolver.java:268) >>> at com.mozilla.SSVDCli.run(SSVDCli.java:89) >>> at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65) >>> at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79) >>> at com.mozilla.SSVDCli.main(SSVDCli.java:129) >>> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) >>> at >> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) >>> at >> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) >>> at java.lang.reflect.Method.invoke(Method.java:597) >>> at org.apache.hadoop.util.RunJar.main(RunJar.java:186) >>> >>> Also, I am using CDH3 with Mahout recompiled to work with CDH3 jars. >>> >>> Thanks >>> Esh >>> >> >>
