[
https://issues.apache.org/jira/browse/HIVE-22269?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Gopal Vijayaraghavan reassigned HIVE-22269:
-------------------------------------------
Assignee: Rajesh Balamohan (was: Gopal Vijayaraghavan)
> Stats miss with "hive.optimize.sort.dynamic.partition"
> (SortedDynPartitionOptimizer) leads to wrong reducer count
> -----------------------------------------------------------------------------------------------------------------
>
> Key: HIVE-22269
> URL: https://issues.apache.org/jira/browse/HIVE-22269
> Project: Hive
> Issue Type: Bug
> Components: Statistics
> Reporter: Rajesh Balamohan
> Assignee: Rajesh Balamohan
> Priority: Minor
> Attachments: HIVE-22269.1.patch, HIVE-22269.2.patch
>
>
> {{hive.optimize.sort.dynamic.partition=true}} introduces new stage to reduce
> number of writes in dynamic partitioning usecase. Earlier
> {{SortedDynPartitionOptimizer}} added this new operator via
> {{Optimizer.java}} and the stats for the newly added operator was populated
> via {{StatsRulesProcFactory$ReduceSinkStatsRule}}.
> However, with "HIVE-20703" this got changed. This is moved to {{TezCompiler}}
> for cost based decision. Though the operator gets added correctly, the stats
> for this does not get added (as it runs after runStatsAnnotation()).
> This causes reducer count to be mis-estimated in the query.
> {noformat}
> e.g For the following query, reducer_2 would be estimated as "2" instead of
> "1009". This causes huge delay in the runtime.
> explain
> from tpcds_xtext_1000.store_sales ss
> insert overwrite table store_sales partition (ss_sold_date_sk)
> select
> ss.ss_sold_time_sk,
> ss.ss_item_sk,
> ss.ss_customer_sk,
> ss.ss_cdemo_sk,
> ss.ss_hdemo_sk,
> ss.ss_addr_sk,
> ss.ss_store_sk,
> ss.ss_promo_sk,
> ss.ss_ticket_number,
> ss.ss_quantity,
> ss.ss_wholesale_cost,
> ss.ss_list_price,
> ss.ss_sales_price,
> ss.ss_ext_discount_amt,
> ss.ss_ext_sales_price,
> ss.ss_ext_wholesale_cost,
> ss.ss_ext_list_price,
> ss.ss_ext_tax,
> ss.ss_coupon_amt,
> ss.ss_net_paid,
> ss.ss_net_paid_inc_tax,
> ss.ss_net_profit,
> ss.ss_sold_date_sk
> where ss.ss_sold_date_sk is not null
> insert overwrite table store_sales partition (ss_sold_date_sk)
> select
> ss.ss_sold_time_sk,
> ss.ss_item_sk,
> ss.ss_customer_sk,
> ss.ss_cdemo_sk,
> ss.ss_hdemo_sk,
> ss.ss_addr_sk,
> ss.ss_store_sk,
> ss.ss_promo_sk,
> ss.ss_ticket_number,
> ss.ss_quantity,
> ss.ss_wholesale_cost,
> ss.ss_list_price,
> ss.ss_sales_price,
> ss.ss_ext_discount_amt,
> ss.ss_ext_sales_price,
> ss.ss_ext_wholesale_cost,
> ss.ss_ext_list_price,
> ss.ss_ext_tax,
> ss.ss_coupon_amt,
> ss.ss_net_paid,
> ss.ss_net_paid_inc_tax,
> ss.ss_net_profit,
> ss.ss_sold_date_sk
> where ss.ss_sold_date_sk is null
> distribute by ss.ss_item_sk
> ;
> {noformat}
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
