[ 
https://issues.apache.org/jira/browse/CASSANDRA-279?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Jonathan Ellis updated CASSANDRA-279:
-------------------------------------

    Attachment: 279-3.patch

Here is a patch on top of sammy's latest that fixes cosmetic issues, removes 
the unused timestamp variable to snapshot, and adds a wait() to the hardlink 
processubuilder.

> finish snapshot support
> -----------------------
>
>                 Key: CASSANDRA-279
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-279
>             Project: Cassandra
>          Issue Type: New Feature
>          Components: Core
>            Reporter: Jonathan Ellis
>            Assignee: Sammy Yu
>         Attachments: 0001-Work-for-CASSANDRA-279.patch, 
> 0001-Work-for-CASSANDRA-279.patch, 0002-Work-for-CASSANDRA-279.patch, 
> 279-3.patch
>
>
> searching for "snapshot" in *.java shows a bunch of code for supporting 
> snapshots via hard links.
> (this works b/c SSTables are immutable, once created.)
> this used to be more complete but when we dropped the JDK7 requirement we 
> just removed the code that we couldn't do in JDK6 and hard link support was 
> one of those.
> So what you would need to do here is:
>  * create a hard link method (using Runtime.exec("ln") on linux / os x I 
> imagine)
>  * add a JMX hook to invoke this on the data files (this is where looking at 
> the old codebase might help); ColumnFamilyStoreMBean.forceFlush is an example 
> of an "Action" jmx interface. using jconsole to interact with JMX stuff is 
> explained here: http://wiki.apache.org/cassandra/MemtableThresholds
>  * add something to list the snapshots available via JMX
>  * optionally make this all per-Table instead of per-database

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.

Reply via email to