cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jimmy Mårdell (JIRA) <j...@apache.org>
Subject [jira] [Commented] (CASSANDRA-8193) Multi-DC parallel snapshot repair
Date Fri, 12 Dec 2014 16:42:13 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-8193?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14244423#comment-14244423
] 

Jimmy Mårdell commented on CASSANDRA-8193:
------------------------------------------

Oh, makes sense. My bad, thanks!

FYI, running (the original) patch - and the other one using active sstables instead of snapshot
ones - in production now and works great.

> Multi-DC parallel snapshot repair
> ---------------------------------
>
>                 Key: CASSANDRA-8193
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-8193
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter: Jimmy Mårdell
>            Assignee: Jimmy Mårdell
>            Priority: Minor
>             Fix For: 2.0.12, 2.1.3
>
>         Attachments: 8193-followup.txt, cassandra-2.0-8193-1.txt, cassandra-2.0-8193-2.txt
>
>
> The current behaviour of snapshot repair is to let one node at a time calculate a merkle
tree. This is to ensure only one node at a time is doing the expensive calculation. The drawback
is that it takes even longer time to do the merkle tree calculation.
> In a multi-DC setup, I think it would make more sense to have one node in each DC calculate
the merkle tree at the same time. This would yield a significant improvement when you have
many data centers.
> I'm not sure how relevant this is in 2.1, but I don't see us upgrading to 2.1 any time
soon. Unless there is an obvious drawback that I'm missing, I'd like to implement this in
the 2.0 branch.



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

Mime
View raw message