The client wants to be able to access cold data (2 years old) in the same cluster so moving data to another system is not possible
However, since we're using Datastax Enterprise, we can leverage Tiered Storage and store old data on Spinning Disks to save on hardware Regards On Tue, Oct 1, 2019 at 9:47 AM Julien Laurenceau <julien.laurenc...@pepitedata.com> wrote: > > Hi, > Depending on the use case, you may also consider storage tiering with fresh > data on hot-tier (Cassandra) and older data on cold-tier (Spark/Parquet or > Presto/Parquet). It would be a lot more complex, but may fit more > appropriately the budget and you may reuse some tech already present in your > environment. > You may even do subsampling during the transformation offloading data from > Cassandra in order to keep one point out of 10 for older data if subsampling > makes sense for your data signal. > > Regards > Julien > > Le lun. 30 sept. 2019 à 22:03, DuyHai Doan <doanduy...@gmail.com> a écrit : >> >> Thanks all for your reply >> >> The target deployment is on Azure so with the Nice disk snapshot feature, >> replacing a dead node is easier, no streaming from Cassandra >> >> About compaction overhead, using TwCs with a 1 day bucket and removing read >> repair and subrange repair should be sufficient >> >> Now the only remaining issue is Quorum read which triggers repair >> automagically >> >> Before 4.0 there is no flag to turn it off unfortunately >> >> Le 30 sept. 2019 15:47, "Eric Evans" <john.eric.ev...@gmail.com> a écrit : >> >> On Sat, Sep 28, 2019 at 8:50 PM Jeff Jirsa <jji...@gmail.com> wrote: >> >> [ ... ] >> >> > 2) The 2TB guidance is old and irrelevant for most people, what you really >> > care about is how fast you can replace the failed machine >> > >> > You’d likely be ok going significantly larger than that if you use a few >> > vnodes, since that’ll help rebuild faster (you’ll stream from more sources >> > on rebuild) >> > >> > If you don’t want to use vnodes, buy big machines and run multiple >> > Cassandra instances in it - it’s not hard to run 3-4TB per instance and >> > 12-16T of SSD per machine >> >> We do this too. It's worth keeping in mind though that you'll still >> have a 12-16T blast radius in the event of a host failure. As the >> host density goes up, consider steps to make the host more robust >> (RAID, redundant power supplies, etc). >> >> -- >> Eric Evans >> john.eric.ev...@gmail.com >> >> --------------------------------------------------------------------- >> 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
