cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jay Zhuang (JIRA)" <>
Subject [jira] [Commented] (CASSANDRA-13095) Timeouts between nodes
Date Thu, 05 Jan 2017 18:19:58 GMT


Jay Zhuang commented on CASSANDRA-13095:

Nice finding. [~aweisberg] could you please review?

I'm not familiar with that. Tried the fix locally, looks good to me. Minor comment: can we
add check to make sure {{sleep}} is larger than 0?

> Timeouts between nodes
> ----------------------
>                 Key: CASSANDRA-13095
>                 URL:
>             Project: Cassandra
>          Issue Type: Bug
>            Reporter: Danil Smirnov
>            Priority: Minor
>         Attachments: 13095-2.1.patch
> Recently I've run into a problem with heavily loaded cluster when sometimes messages
between certain nodes become blocked with no reason.
> It looks like the same situation that described here
> Thread dump showed infinite loop here:
> Apparently the problem is in the initial value of epoch filed in TimeHorizonMovingAverageCoalescingStrategy
class. When it's value is not evenly divisible by BUCKET_INTERVAL, ix(epoch-1) does not point
to the correct bucket. As a result, sum gradually increases and, upon reaching MEASURED_INTERVAL,
averageGap becomes 0 and thread blocks.
> It's hard to reproduce because it takes a long time for sum to grow and when no messages
are send for some time, sum becomes 0
and bug is no longer reproducible (until connection between nodes is re-created).
> I've added a patch which should fix the problem. Don't know if it would be of any help
since CASSANDRA-12676 will apparently disable this behaviour. One note about performance regressions
though. There is a small chance it being result of the bug described here, so it might be
worth testing performance after fixes and/or tuning the algorithm.

This message was sent by Atlassian JIRA

View raw message