Re: [jgroups-users] JGroups failing to give up on crashed coordinator

Hi Jim,

I highly recommend *not* using FLUSH, as it was written a long time ago, 
has never been really used in production and is prone to blocking! Do 
you really need virtual synchrony?

Oftentimes, similar properties can be achieved using application level 
mechanisms, e.g. TXs, or switching to total order (SEQUENCER).

Also note that MERGE3 got changed in 3.6.12 to cover an additional edge 
case [1].

If you run into this again *without using FLUSH* and the MERGE3 from 
3.6.12; I'll take a look...

[1] https://issues.jboss.org/browse/JGRP-2128

On 13/12/16 00:19, Questions/problems related to using JGroups wrote:
> Hi Bela,
>
> We made some improvements to the network and hardware and things have
> been much more reliable.  3.6.11.Final seemed to really help with some
> of the merging problems that we were still having.  However we still
> manage to get a condition where a node just won't give up on a view with
> a coordinator who has moved on to a new view which does not include it.
> In this case the coordinator (node_1) is installing a new view that does
> not include node_9 which it rejects and then it seems to be stuck
> forever (or at least way longer than I'm waiting for it to fix itself).
> Here is a log from node_9 with some commentary inline:

> I'm wondering what condition has to occur for the coordinator to drop
> node_9 from the view and node_9 being oblivious.  Is there a setting
> that I could change that will cause this to recover faster, or at all?
> Or should JGroups be checking to see if the rejected view is coming from
> our coordinator and do something other than just dropping it?
>
> Thanks
> JT
> _______________________________________________
> javagroups-users mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/javagroups-users


-- 
Bela Ban, JGroups lead (http://www.jgroups.org)


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