You are viewing a plain text version of this content. The canonical link for it is here.

Posted to commits@cassandra.apache.org by "xiangzhou xia (JIRA)" <ji...@apache.org> on 2017/08/11 01:46:00 UTC

[jira] [Created] (CASSANDRA-13756) StreamingHistogram is not thread safe

xiangzhou xia created CASSANDRA-13756:
-----------------------------------------

             Summary: StreamingHistogram is not thread safe
                 Key: CASSANDRA-13756
                 URL: https://issues.apache.org/jira/browse/CASSANDRA-13756
             Project: Cassandra
          Issue Type: Bug
            Reporter: xiangzhou xia


optimization in CASSANDRA-13038 led to a spool flush every time when we call sum. Since TreeMap is not thread safe, threads will be stuck when multiple threads visit sum() at the same time, and finally 100% cpu is stuck in that function. 

I think this issue is not limit to sum(), update() and merge() both have the same issue since they all need to update TreeMap. 

Add lock to bin solved this issue but it also introduced extra overhead.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org
For additional commands, e-mail: commits-help@cassandra.apache.org