Can I ask you an additional question here? How much free space should I have if most tables use TimeWindowCompactionStrategy?
> On 13 Jul 2018, at 10:09 PM, Vitaliy Semochkin <vitaliy...@gmail.com> wrote: > > Jeff, thank you very much for reply. > Will try to use 4TB per instance. > > If I understand it correctly level compaction can lead to 50% > https://docs.datastax.com/en/dse-planning/doc/planning/planningHardware.html > > Regarding the question of running multiple instances per server, am I > correct that in case of 3.11 instances and having several disks > dedicated for each instance, running multiple instances per server is > ok? > > > On Thu, Jul 12, 2018 at 5:47 PM Jeff Jirsa <jji...@gmail.com> wrote: >> >> You can certainly go higher than a terabyte - 4 or so is common, Ive heard >> of people doing up to 12 tb with the awareness that time to replace scales >> with size on disk, so a very large host will take longer to rebuild than a >> small host >> >> The 50% free guidance only applies to size tiered compaction, and given your >> throughput you may prefer leveled compaction anyway. With leveled you should >> target 30% free for compaction and repair >> >> You don’t need more than one Cassandra instance per host for 4tb but you may >> want to consider it for more than that - multiple instances are especially >> useful if you have multiple (lots of) disks and are running Cassandra before >> CASSANDRA-6696 (which made jbod safer). >> >> -- >> Jeff Jirsa >> >> >>> On Jul 12, 2018, at 7:37 AM, Vitaliy Semochkin <vitaliy...@gmail.com> wrote: >>> >>> Hi, >>> >>> Which amount of data Cassandra 3 server in a cluster can serve at max? >>> The documentation says it is only 1TB. >>> If the load is not high (only about 100 requests per second with 1kb >>> of data each) is it safe to go above 1TB size (let's say 5TB per >>> server)? >>> What will be safe maximum disk size a server in such cluster can serve? >>> >>> Documentation also says that compaction requires to have %50 of disk >>> occupied space. In case I don't have update operations (only insert) >>> do I need that much extra space for compaction? >>> >>> In articles (outside Datastax docs) I read that it is a common >>> practice to launch more than one Cassandra server on one physical >>> server in order to be able use more than 1TB of hard driver per >>> server, is it recommended? >>> >>> --------------------------------------------------------------------- >>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org >>> For additional commands, e-mail: user-h...@cassandra.apache.org >>> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org >> For additional commands, e-mail: user-h...@cassandra.apache.org >> > > --------------------------------------------------------------------- > To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > For additional commands, e-mail: user-h...@cassandra.apache.org >
