Apart from logging, given enough memory, you could get Cassandra to behave almost like an in-memory system.
Turning off logging is relatively straightforward. If you turn off periodic flushing of memtables and have the thresholds high enough (a little more tricky), you're done -- chances are the read path and the write path will never hit disk. On Wed, Jun 3, 2009 at 5:48 PM, Jonathan Ellis <[email protected]> wrote: > Cassandra is not designed to work memory-only. It's designed designed > to use disk for durability and to accommodate using large sets of > data, letting the OS use memory as a huge cache for that. For typical > data use patterns (where a relatively small amount is "hot") this will > be a much better use of hardware than memory-only. > > On Wed, Jun 3, 2009 at 7:44 PM, lichun li <[email protected]> wrote: >> Thank you! >> The "how fast is it" section says:"In a nutshell, Cassandra is much >> faster than relational databases, and much slower than memory-only >> systems or systems that don't sync each update to disk." >> Can Cassandra work in a memory-only mode? Can it be done by just >> changing configuration? >> >> On Wed, Jun 3, 2009 at 10:38 PM, Jonathan Ellis <[email protected]> wrote: >>> We're basically in a roll-your-own benchmark state. Johan can >>> probably give some pointers: >>> http://blog.oskarsson.nu/2009/05/vpork.html. Also see the "how fast >>> is it" section here: >>> http://spyced.blogspot.com/2009/05/cassandra-03-release-candidate-and.html >>> >>> -Jonathan >>> >>> On Wed, Jun 3, 2009 at 3:06 AM, lichun li <[email protected]> wrote: >>>> I can't find cassandra's performance data, such as throughput. Does >>>> anyone know where to find these data? >>>> >>>> -- >>>> Sincerely yours, >>>> >>>> Lichun Li >>>> Mobile Life New Media Lab, BUPT >>>> >>> >> >> >> >> -- >> Sincerely yours, >> >> Lichun Li >> Mobile Life New Media Lab, BUPT >> >
