Thanks to Shujie for helpful reply. Yes, it is transparent to upper logics which following Volcano model to evaluate cost and generate plan. When we finish the vectorization work (mostly), we may seek for a Vectorization-aware QO, with consider Bach-a-time, or Operatior-a-time, rather than Tuple-a-time.
-------------—— Kuien Liu/奎恩 ------------------------------------------------------------------发件人：Shujie Zhang <[email protected]>发送时间：2018年2月27日(星期二) 09:41收件人：dev <[email protected]>; 刘奎恩(局外) <[email protected]>主 题：Re: a vectorized execution design document Hi, We check the plan node to see if it can be vectorized when the Plan has been generated, In this phase, the only cheapest Plan had been selected, so we have no chance to change it. If we want to generate the vectorized Plan in the optimizer, we should generate the vectorized Path and compute the cost of it, then we can compare with both the cost of them and choose the cheaper one, the trouble is both build-in-optimizer and ORCA should be refactored, it is a complex work:). Another trouble is that the solution space of optimizer would become larger becuase of adding a new type Path, the planning time should be controlled. In this design, we change the Plan after it was generated, it is transparent to upper modules, so the optimizer is also can be changed to fit the current vectorized Plan in the future. Thanks,Zhang Shujie On Mon, Feb 26, 2018 at 3:01 PM, 刘奎恩(局外) <[email protected]> wrote: Nice doc, clear design. It is a good start ! I saw an example on aggregation is illustrated during the doc, we may implement more operators with this design, for example, SORT, JOIN. One question is: we implement vectorization under plan three, that is, the optimizer cannot feel the change in this way, it still estimates overall cost like ' total_cost = startup_cost + cpu_per_tuple * tuples + seq_page_cost * pages 'In my opinion, the second part (CPU costs) changes a lot, so it is should be a stage design, any further plan on it? -------------—— Kuien Liu/奎恩 ------------------------------------------------------------------发件人：Shujie Zhang <[email protected]>发送时间：2018年2月9日(星期五) 16:35收件人：dev <[email protected]>主 题：a vectorized execution design document Hi, A vectorized execution design document have been uploaded to the issue#1450: https://issues.apache.org/jira/browse/HAWQ-1450 Inside the document are a lot of ideas about how to implement a vectorized executor, We welcome any comments on the content and suggestions for improvement, thanks. Zhang Shujie 2018-02-09
