No worry for overlapping, the use-case is about events/timeseries and there is almost no delay so it should be fine.
On the note-side, since we have the guarantee to have 1 SSTable/day of ingestion, this is very easy to "emulate" incremental backup. You just need to find the generated SSTable with the latest create date and back it up every day at midnight with a script. Purging data is also straightforward, just dropping SSTables (by a script) where create date is older than a threshold, we don't even need to rely on TTL On Mon, Feb 11, 2019 at 9:19 PM Jeff Jirsa <jji...@gmail.com> wrote: > Wild ass guess based on a large use case I knew about at the time > > If you go above that, I expect it’d largely be fine as long as you were > sure they weren’t overlapping so reads only ever touched a small subset of > the windows (ideally 1). > > If you have one day windows and every read touches all of the windows, > you’re going to have a bad time. > > -- > Jeff Jirsa > > > On Feb 11, 2019, at 12:12 PM, DuyHai Doan <doanduy...@gmail.com> wrote: > > Hello users > > On the official documentation for TWCS ( > http://cassandra.apache.org/doc/latest/operating/compaction.html#time-window-compactionstrategy) > it is advised to select the windows unit and size so that the total number > of windows intervals is around 20-30. > > Is there any explanation for this range of 20-30 ? What if we exceed this > range, let's say having 1 day windows and keeping data for 1year, thus > having indeed 356 intervals ? What can go wrong with this ? > > Regards > > Duy Hai DOAN > >
