[jboss-jira] [JBoss JIRA] (JGRP-1317) Compress Digest and MutableDigest

[Bela Ban (JIRA)]

    [ https://issues.jboss.org/browse/JGRP-1317?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12803046#comment-12803046 ] 

Bela Ban edited comment on JGRP-1317 at 9/10/13 9:12 AM:
---------------------------------------------------------

In GMS.GmsHeader, the following cases allow for merging the view and digest:
* JOIN_RSP (implemented in JoinRsp): DONE
* MERGE_RSP: DONE
* INSTALL_MERGE_VIEW: DONE

VIEW isn't one of them, as it doesn't carry a digest: view changes are sent to existing members, only JoinRsps sent to joiners carry a digest.
                
      was (Author: belaban):
    In GMS.GmsHeader, the following cases allow for merging the view and digest:
* JOIN_RSP (implemented in JoinRsp): DONE
* MERGE_RSP: DONE
* INSTALL_MERGE_VIEW

VIEW isn't one of them, as it doesn't carry a digest: view changes are sent to existing members, only JoinRsps sent to joiners carry a digest.
                  
> Compress Digest and MutableDigest
> ---------------------------------
>
>                 Key: JGRP-1317
>                 URL: https://issues.jboss.org/browse/JGRP-1317
>             Project: JGroups
>          Issue Type: Feature Request
>            Reporter: Bela Ban
>            Assignee: Bela Ban
>             Fix For: 3.4
>
>
> For large clusters, STABLE messages are quite large, and should be compressed to be sent over the wire. 
> STABLE messages are sent between members in the same view, so we could only send the ViewId + highest_delivered/highest_received seqnos.
> Everybody who receives a STABLE message grabs the View associated with the ViewId (should be the current view !) and creates a Digest based on the View and the long[] array.
> Further optimization:
> - Canonicalize digests: if everyone has (14) 20, 22, then we could write it once, give it an ID of (say) 1 and then only refer to 1 again if we encounter the same digest. Actually, as a matter of fact, most of the digests would be the same, so this optimization could have a big effect !

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira