Map/reduce is known to be slower than a standard fetch, so what you're experiencing is likely a direct result of m/r overhead.
I would be interested in seeing if your test case shows a notable speed difference against the current official release of Riak (0.14.2 I believe). Based on what I've read of the in-development changes, performance should be worse in the 0.14.2 release (assuming that the new m/r functionality based on Riak Pipe is merged into whichever branch you're using). I may be worth testing just to make sure you're not seeing worse performance (which could suggest a new bug has been introduced). * <http://www.loomlearning.com/> Jonathan Langevin Systems Administrator Loom Inc. Wilmington, NC: (910) 241-0433 - jlange...@loomlearning.com - www.loomlearning.com - Skype: intel352 * On Tue, Aug 30, 2011 at 3:06 PM, Mark Steele <mste...@beringmedia.com>wrote: > I'm actually testing with an object that has only one link as that's my > use-case. > > In testing, 2 separate gets is way faster than using a map-reduce > link-walk, which is disappointing :( > > I'm also testing on a one node cluster, and my bucket has a N/R/W=1. I was > thinking that the reduction in network hops would outweigh the map reduce > overhead, but apparently that's not the case. > > Simple get (one value) : 0.000741 > Multiget linkwalk (get one object, then link walk in php) : 0.001567 > Linkwalk (map reduce): 0.041994 > > The map phase does not significantly change anything as far as performance. > > In case it matters, I'm testing against the latest riak code on github. > > Cheers, > > Mark Steele > Bering Media Inc. > > On Tue, Aug 30, 2011 at 3:00 PM, Jonathan Langevin < > jlange...@loomlearning.com> wrote: > >> Good catch Kev. >> >> Mark, If you run the same operation with map removed, what is the >> performance at that point?* >> >> <http://www.loomlearning.com/> >> Jonathan Langevin >> Systems Administrator >> Loom Inc. >> Wilmington, NC: (910) 241-0433 - jlange...@loomlearning.com - >> www.loomlearning.com - Skype: intel352 >> * >> >> >> >> On Tue, Aug 30, 2011 at 2:45 PM, Kev Burns <kevburn...@gmail.com> wrote: >> >>> Mark, >>> >>> That's not just a link walk, you're also performing a map operation >>> there. >>> >>> $client->add($bucketname, 'linkkey1')-> >>> link()-> >>> map(array("riak_kv_mapreduce", "map_object_value")) -> >>> run(); >>> >>> >>> If the expected number of returned objects is small, performing the map >>> phase in PHP may be faster. >>> >>> - Kev >>> c: +001 (650) 521-7791 >>> >>> >>> On Tue, Aug 30, 2011 at 7:31 AM, Mark Steele <mste...@beringmedia.com>wrote: >>> >>>> Hi folks, >>>> >>>> Just want to know if I'm doing something obviously dumb here. >>>> >>>> First the (PHP) code (Sorry of the API is different from the official >>>> API, we're using a heavily modified version): >>>> >>>> <snip> >>>> $obj1 = $bucket->newObject('linkkey1', array('link1')); >>>> $obj2 = $bucket->newObject('linkkey2', 'dataforlinkkey2'); >>>> $obj1->addLink($obj2); >>>> $obj2->addLink($obj1); >>>> $obj1->store(); >>>> $obj2->store(); >>>> >>>> $start = microtime(true); >>>> $blargh = $bucket->get('linkkey2'); >>>> $end = microtime(true); >>>> printf("Took : %04f\n",$end - $start); >>>> >>>> $start = microtime(true); >>>> $result = >>>> $client->add($bucketname, 'linkkey1')-> >>>> link()-> >>>> map(array("riak_kv_mapreduce", "map_object_value")) -> >>>> run(); >>>> foreach ($result as $data) { >>>> //var_dump($data); >>>> } >>>> $end = microtime(true); >>>> printf("Took : %04f\n",$end - $start); >>>> <snip> >>>> >>>> So here's what I'm seeing: >>>> >>>> The simple key fetch takes 0.000661 seconds to execute, whereas the >>>> link-walk takes 0.042043. Ouch. Quite a bit slower. Any ways to speed >>>> this up? >>>> >>>> Cheers, >>>> >>>> Mark Steele >>>> Bering Media Inc. >>>> >>>> >>>> _______________________________________________ >>>> 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 >>> >>> >> >
_______________________________________________ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
