8 is too small. Try 32 or the default, 64.
@siculars http://siculars.posterous.com Sent from my iRotaryPhone On Nov 21, 2012, at 14:10, "Cornelius Schmale" <s...@fh-wedel.de> wrote: > Hi Bryan, > > thanks for your excellent answer, it helped a lot for a deeper knowledge of > riak. > > You are right, I am using the default-one-node development cluster. After > decreasing the ring size to 8 as mentioned by you, everything works fine. > > I will post your answer unter my question at Stackoverflow, if it is ok for > you? > > Thanks a lot, > Cornelius > > -- > Cornelius Schmale > FH Wedel Gemeinnützige Schulgesellschaft mbH Feldstraße 143, 22880 Wedel > Tel.: +49 4103 8048-736 > E-Mail: s...@fh-wedel.de > Web: http://www.fh-wedel.de/ > > Sitz der Gesellschaft: Wedel > Registergericht: Amtsgericht Pinneberg HRB 1578 > Geschäftsführung: Prof. Dr. Eike Harms > > > -----Ursprüngliche Nachricht----- > Von: Bryan Fink [mailto:br...@basho.com] > Gesendet: Montag, 19. November 2012 16:07 > An: Cornelius Schmale > Cc: riak-users@lists.basho.com > Betreff: Re: Pipe worker startup failed:fitting was gone before startup > > On Mon, Nov 12, 2012 at 12:04 PM, Cornelius Schmale <s...@fh-wedel.de> wrote: >> I have some problems using riak and mapreduce queries. I’ve described >> the hole problem at >> >> http://stackoverflow.com/questions/13345448/riak-fails-at-mapreduce-qu >> eries-which-configuration-to-use > > Hi, Cornelius. Could you describe a bit, your Riak configuration? > Specifically, how many nodes are in your cluster, and what is the > ring_creation_size from you app.config? > > If, for example, you're using a default setup {ring_creation_size, 64} on a > one-node development cluster, this behavior is quite likely. > 155,000 items is enough to get all 64 vnodes working. > > In the first case, before raising map_js_vm_count, those 64 vnodes are > fighting over just 8 Javascript VMs, and so some are likely to be starved > long enough to time out, which will cause the "All VMs are busy" log message. > > In the second case, after raising map_js_vm_count, it's likely that those 36 > Javascript VMs just aren't able to process all 155,000 items before the query > timeout arrives. The "fitting was gone before startup" log message is saying > that pipe running the query shut down while there were still inputs arriving > at vnodes. > > You're not seeing either of these behaviors in the simple case with no map > function because no interaction with Javascript VMs is required. > In addition, for that case, objects are not even read off of disk, further > alleviating resource contention. > > The two configuration solutions I expect will help the most are lowering > ring_creation_size, and raising the query timeout. Lowering > ring_creation_size to 16, or even 8 on a single-node cluster will cause less > contention for Javascript VMs because there will be less attempted > parallelism in the map function processing. Raising the query timeout (should > be an argument to the 'run' function, or similar, but I'm not familiar with > the riak-js client), will give the query more time to finish before shutting > down, which may be necessary to overcome slow processing. > > Rewriting your map function in Erlang should also help, since it will be > faster, and will not have the same sort of VM contention. But, I understand, > that's not as easy to using in early-stage development. > > HTH, > Bryan > > > > _______________________________________________ > riak-users mailing list > riak-users@lists.basho.com > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com _______________________________________________ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
