RE: [Multi DC] Old Data Not syncing from Existing cluster to new Cluster

But how I will tell rebuild command source DC if I have more than 2 Dc? @dinking, yes I run the command, and it did some strange thing now: Datacenter: DRPOCcluster Status=Up/Down |/ State=Normal/Leaving/Joining/Moving -- AddressLoad Tokens Owns

Re: Time series data model and tombstones

In theory, you're right and Cassandra should possibly skip reading cells having time < 50. But it's all theory, in practice Cassandra read chunks of xxx kilobytes worth of data (don't remember the exact value of xxx, maybe 64k or far less) so you may end up reading tombstones. On Sun, Jan 29,

Re: Time series data model and tombstones

Check out our post on how to use TWCS before 3.0. http://thelastpickle.com/blog/2017/01/10/twcs-part2.html On Sun, Jan 29, 2017 at 11:20 AM John Sanda wrote: > It was with STCS. It was on a 2.x version before TWCS was available. > > On Sun, Jan 29, 2017 at 10:58 AM DuyHai

Re: Time series data model and tombstones

Thanks for the clarification. Let's say I have a partition in an SSTable where the values of time range from 100 to 10 and everything < 50 is expired. If I do a query with time < 100 and time >= 50, are there scenarios in which Cassandra will have to read cells where time < 50? In particular I am

Re: Time series data model and tombstones

"Should the data be sorted by my time column regardless of the compaction strategy" --> It does What I mean is that an old "chunk" of expired data in SSTABLE-12 may be compacted together with a new chunk of SSTABLE-2 containing fresh data so in the new resulting SSTable will contain tombstones

Re: Time series data model and tombstones

> > Since STCS does not sort data based on timestamp, your wide partition may > span over multiple SSTables and inside each SSTable, old data (+ > tombstones) may sit on the same partition as newer data. Should the data be sorted by my time column regardless of the compaction strategy? I didn't

Re: Time series data model and tombstones

Ok so give it a try with TWCS. Since STCS does not sort data based on timestamp, your wide partition may span over multiple SSTables and inside each SSTable, old data (+ tombstones) may sit on the same partition as newer data. When reading by slice, even if you request for fresh data, Cassandra

Re: Time series data model and tombstones

It was with STCS. It was on a 2.x version before TWCS was available. On Sun, Jan 29, 2017 at 10:58 AM DuyHai Doan wrote: > Did you get this Overwhelming tombstonne behavior with STCS or with TWCS ? > > If you're using DTCS, beware of its weird behavior and tricky >

Re: Time series data model and tombstones

Did you get this Overwhelming tombstonne behavior with STCS or with TWCS ? If you're using DTCS, beware of its weird behavior and tricky configuration. On Sun, Jan 29, 2017 at 3:52 PM, John Sanda wrote: > Your partitioning key is text. If you have multiple entries per id

Re: Time series data model and tombstones

> > Your partitioning key is text. If you have multiple entries per id you are > likely hitting older cells that have expired. Descending only affects how > the data is stored on disk, if you have to read the whole partition to find > whichever time you are querying for you could potentially hit

Re: Time series data model and tombstones

Your partitioning key is text. If you have multiple entries per id you are likely hitting older cells that have expired. Descending only affects how the data is stored on disk, if you have to read the whole partition to find whichever time you are querying for you could potentially hit tombstones