You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@kudu.apache.org by "Todd Lipcon (JIRA)" <ji...@apache.org> on 2016/03/27 08:30:25 UTC

[jira] [Created] (KUDU-1380) Scanners rewind to beginning of the tablet on SERVER_TOO_BUSY

Todd Lipcon created KUDU-1380:
---------------------------------

             Summary: Scanners rewind to beginning of the tablet on SERVER_TOO_BUSY
                 Key: KUDU-1380
                 URL: https://issues.apache.org/jira/browse/KUDU-1380
             Project: Kudu
          Issue Type: Bug
    Affects Versions: 0.7.1
            Reporter: Todd Lipcon
            Priority: Blocker


When a scanner receives ERROR_SERVER_TOO_BUSY from an overloaded TS, the CanBeRetried() function indicates that it is safe to retry. However, this ends up calling through to ReopenCurrentTablet() which rewinds back to the start of the tablet in the case that the scan wasn't marked as fault-tolerant.

In the case of a lot of concurrent TPCH Q6 queries via Impala, this ended up resulting in "never-ending" queries - each scanner was likely to hit the occasional TOO_BUSY error and start back at the beginning.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)