Brian The comments in the ycombinator.com link are correct about leveldb stalling during writes. That is an unacceptable trait for Riak. We have a custom branch available to everyone at github.com: "basho/leveldb". The branch contains all code changes through 1.9 of Google's code. It also contains our tunings to increase leveldb's performance / throughput into terabyte scenarios. The stalls are now mitigated via progressive write throttling if leveldb gets too far behind in its background work. The throttling rate is self tuning to the environment and work load. We have tested on SATA, SSD, and FusionIO semiconductor arrays. All work great.
Matthew On May 3, 2013, at 2:43 PM, Kresten Krab Thorup <[email protected]> wrote: > I tried lmdb in an iOS project recently and while it is indeed fast i also > did run into several issues. I needed something seriously faster than SQLite > and after some experimentation ended up embedding leveldb in stead. > > 1. When storing objects larger than the page size (default is 4k) then those > pages are not taken from the free list (since they need to be consecutive) > but always adds to the file size. This means you can easily run out of space. > > 2. The fact that it can only have one write transaction open means that you > have to be very careful in not causing serious lock congestion. > > So in my experience it only makes sense to use in a read-heavy application > with mostly small values. > > Kresten > > Sent from my iPhone > > On 01/05/2013, at 19.06, "Brian Hong" > <[email protected]<mailto:[email protected]>> wrote: > > OpenLDAP Lightning Memory-Mapped Database seems to be getting traction for > it's high performance and similar query (iteration) functionality with > leveldb: > http://symas.com/mdb/ > > There seems to be an experimental backend for Riak: > > https://github.com/alepharchives/emdb > > Does anybody know of it's usefulness? Is there any benchmarks on it? > > I've heard that leveldb suffers write performance issues: > https://news.ycombinator.com/item?id=5621884 > > Any chances of Basho guys supporting lmdb as an leveldb alternative to Riak? > It would be awesome! :D > > -- > Brian(Sung-jin) Hong > _______________________________________________ > riak-users mailing list > [email protected]<mailto:[email protected]> > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com > _______________________________________________ > riak-users mailing list > [email protected] > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com _______________________________________________ riak-users mailing list [email protected] http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
