Re: [Discussion] Code generation in carbon result preparation

2016-10-14 Thread Vimal Das Kammath
Hi Vishal, I think, we need both solution 1 & 2 Solution1 may need re-desiging several parts of Carbon's query process starting from scanner, aggregator to result preparation. This can help avoid the frequent cache invalidation. In Solution2 code generation will not solve the frequent cache inva

Re: [Discussion] Code generation in carbon result preparation

2016-10-12 Thread Aniket Adnaik
Hi Vishal, In general, it is good idea to have a cache efficient algorithm. For solution-1 : how do you want to handle variable length columns and nulls? may be you will have to maintain variable length columns separately and use offsets ? For solution 2: code generation may be more efficient

Re: [Discussion] Code generation in carbon result preparation

2016-10-12 Thread Kumar Vishal
Hi Jacky, Yes result preparation in exeutor side. -Regards Kumar Vishal On Wed, Oct 12, 2016 at 9:33 PM, Jacky Li wrote: > Hi Vishal, > > Which part of the preparation are you considering? The column stitching in > the executor side? > > Regards, > Jacky > > > 在 2016年10月12日,下午9:24,Kumar Vishal

Re: [Discussion] Code generation in carbon result preparation

2016-10-12 Thread Jacky Li
Hi Vishal, Which part of the preparation are you considering? The column stitching in the executor side? Regards, Jacky > 在 2016年10月12日,下午9:24,Kumar Vishal 写道: > > Hi All, > Currently we are preparing the final result row wise, as number of columns > present in project list(80 columns) is hig

[Discussion] Code generation in carbon result preparation

2016-10-12 Thread Kumar Vishal
Hi All, Currently we are preparing the final result row wise, as number of columns present in project list(80 columns) is high mainly measure column or no dictionary column there are lots of cpu cache invalidation is happening and this is resulting to slower the query performance. *I can think of