I dont know the meaning in_memory=false in context of phoenix. In context of hbase, that entire data will be kept in memory( not just block cache). I m guessing, Phoenix is also doing same thing. By data size on disk, you can roughly estimate memory footprint. For example, You can load one index into memory by setting in_memory flag and see how much memory it took. Then u can estimate memory usage for other index on basis of your experiment.
Sent from my iPhone > On Mar 22, 2016, at 9:05 AM, Sumit Nigam <[email protected]> wrote: > > Thank you Anil. > > Any inputs on what does IN_MEMORY = false do at index creation time? > > I get the separate table part. But not sure I understood why would memory > footprint be equal to data size. Would this secondary index reside entirely > in memory? I guess only parts of it would reside on block cache, right? > > Thanks for such a prompt reply. > Sumit > > > > From: anil gupta <[email protected]> > To: "[email protected]" <[email protected]>; Sumit Nigam > <[email protected]> > Sent: Tuesday, March 22, 2016 9:11 PM > Subject: Re: Secondary index memory footprint > > Global indexes are stored in a separate hbase table. So, you can estimate > memory footprint by looking at the data size of that index currently. > > HTH, > Anil Gupta > > On Tue, Mar 22, 2016 at 7:19 AM, Sumit Nigam <[email protected]> wrote: > Hi, > > I am trying to estimate what (if any) are the implications of accumulating > data in phoenix secondary index. I have a secondary index on 3 columns and > would like to know if anyone has an idea of how to estimate memory footprint > of secondary index (if any) based on number of entries in data table. The > index is global and not local. > > Plus, what is the impact of setting IN_MEMORY=true when index is created? > > Thanks, > Sumit > > > > -- > Thanks & Regards, > Anil Gupta > >
