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Aman Sinha commented on IMPALA-8962: ------------------------------------ [~guojingfeng] Thanks for reporting the issue with fetch_rows_timeout_ms. Based on internal investigation the empty results (or sometimes partial results) with the JDBC/ODBC driver is indeed a problem and we are pursuing this with the driver provider. In the meantime, it is best to set the value of fetch_rows_timeout_ms = 0. I will create a JIRA for reverting this to 0 since we cannot be sure what other drivers may be affected with the non-blocking mode. > FETCH_ROWS_TIMEOUT_MS should apply before rows are available > ------------------------------------------------------------ > > Key: IMPALA-8962 > URL: https://issues.apache.org/jira/browse/IMPALA-8962 > Project: IMPALA > Issue Type: Bug > Components: Clients > Reporter: Sahil Takiar > Assignee: Sahil Takiar > Priority: Major > Fix For: Impala 3.4.0 > > > IMPALA-7312 added a fetch timeout controlled by the query option > {{FETCH_ROWS_TIMEOUT_MS}}. The issue is that the timeout only applies after > the *first* batch of rows are available. The issue is that both Beeswax and > HS2 clients call {{request_state->BlockOnWait}} inside > {{ImpalaServer::FetchInternal}}. The call to {{BlockOnWait}} blocks until > rows are ready to be consumed via {{ClientRequestState::FetchRows}}. > So clients can still end up blocking indefinitely waiting for the first row > batch to appear. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org