On 20 Dec 2010, at 23:20, Sebastian Cohnen wrote: > question inside :) > > On 20.12.2010, at 23:02, Jan Lehnardt wrote: > >> Hi, >> >> On 20 Dec 2010, at 22:32, Chenini, Mohamed wrote: >> >>> Hi, >>> >>> I found this info on the net at >>> http://www.slideshare.net/danglbl/schemaless-databases >>> [...] >>> Does anyone knows if this was verified? >> >> I think the author's comment on slide 35 sums it up pretty nicely: >> >> "Of course this is just one (lame) test." >> >> Coming up good numbers is hard which means that people with easy ways to >> make them come up with bad ones. >> >> I've written about the difficulties on benchmarks databases on my blog: >> >> http://jan.prima.de/~jan/plok/archives/175-Benchmarks-You-are-Doing-it-Wrong.html >> http://jan.prima.de/~jan/plok/archives/176-Caveats-of-Evaluating-Databases.html >> >> They should give you a few pointers on why this is hard. >> >> -- >> >> To the point: CouchDB generally performs best with concurrent load. In the >> case of loading data into CouchDB, bulk requests* will speed up things >> again. To push CouchDB to a write limit, you want to use concurrent bulk >> requests (specific numbers will depend on your data and hardware). > > Does this really speed up things? I've tried this approach (concurrent bulk > inserts) with small/big docs and small/big bulk chunk sizes: the difference > was not significant. I thought this was reasonable, since writes are > serialized anyways. The setup was one box generating documents, creating > bulks and keep them in memory and bulk insert batches of complete docs (incl. > simple monotonic increasing ints as doc ids) to another node. delayed commit > was off.
Have you tested these against single doc inserts? Cheers Jan -- > >> >> * http://wiki.apache.org/couchdb/HTTP_Bulk_Document_API >> >> Unfortunately this means that these one-off benchmarks don't show any good >> numbers for CouchDB, yet fortunately this shows easily that these one-off >> benchmarks don't really reflect common real-world usage and should be >> discouraged. >> >> Hope that helps, let us know if you have any more questions :) >> >> Cheers >> Jan >> -- >> >
