Besides the others' advice that 2000+ keyspaces might be too much, the latest Java driver (2.0.11) includes an option to disable the Metadata API http://www.datastax.com/dev/blog/datastax-java-driver-2-0-11-released. I'm not sure at this moment if this has been merged into 2.1 already.
On Sun, Sep 20, 2015 at 9:22 AM, joseph gao <gaojf.bok...@gmail.com> wrote: > cassandra: 2.1.7 > java driver: datastax java driver 2.1.6 > > Here is the problem: > My application uses 2000+ keyspaces, and will dynamically create > keyspaces and tables. And then in java client, the > Metadata.tokenMap.tokenToHost would use about 1g memory. so this will cause > a lot of full gc. > As I see, the key of the tokenToHost is keyspace, and the value is a > tokenId_to_replicateNodes map. > > When I try to solve this problem, I find something not sure: all > keyspaces have same 'tokenId_to_replicateNodes' map. > My replication strategy of all keyspaces is : simpleStrategy and > replicationFactor is 3 > > So would it be possible if keyspaces use same strategy, the value of > tokenToHost map use a same map. So it would extremely reduce the memory > usage > > thanks a lot > > -- > ------ > Joseph Gao > PhoneNum:15210513582 > QQ: 409343351 > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax <http://cassandrasummit-datastax.com/?utm_campaign=summit15&utm_medium=summiticon&utm_source=emailsignature>
