Samarth Jain created PHOENIX-1779:
-------------------------------------
Summary: Parallelize fetching of next batch of records for scans
corresponding to queries with no order by
Key: PHOENIX-1779
URL: https://issues.apache.org/jira/browse/PHOENIX-1779
Project: Phoenix
Issue Type: Improvement
Reporter: Samarth Jain
Assignee: Samarth Jain
Today in Phoenix we parallelize the first execution of scans i.e. we load only
the first batch of records up to the scan's cache size in parallel. Loading of
subsequent batches of records in scanners is essentially serial. This could be
improved especially for queries, including the ones with no order by clauses,
that do not need any kind of merge sort on the client. This could also
potentially improve the performance of UPSERT SELECT statements that load data
from one table and insert into another. One such use case being creating
immutable indexes for tables that already have data. It could also potentially
improve the performance of our MapReduce solution for bulk loading data by
improving the speed of the loading/mapping phase.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
