Thank you all for the responses.

When we put the ERJGroupsSynchronizer in production we started receiving 
reports of users not being able to access the application instances or getting 
kicked out of the application.  I do not know if the ERJGroupsSynchronizer is 
the one to blame.  So I think it would be unfair to blame the problem on 
ERJGroupsSynchronizer.

We just noticed the these warnings in the console and the first thing we tried 
was to disable the synchronizer and the problem seems like it disappeared after 
we did that.  

Mar 11, 2022 12:14:10 AM org.jgroups.protocols.UDP setBufferSize
WARNING: JGRP000015: the send buffer of socket MulticastSocket was set to 5MB, 
but the OS only allocated 212.99KB. This might lead to performance problems. 
Please set your max send buffer in the OS correctly (e.g. net.core.wmem_max on 
Linux)

This seems like it could be fixed by increasing the max send buffer on the 
servers.

The testers in our UAT environment noticed the following warnings:

WARNING: JGRP000012: discarded message from different cluster UATClaimScrubber 
(our cluster is UATContractManager). Sender was 
f677bf19-c5e7-a69e-2000-97638a06f579 (received 4 identical messages from 
f677bf19-c5e7-a69e-2000-97638a06f579 in the last 64665 ms)

I think this just means that two different instances with a different 
application name are using the same multicast address.  Nothing really harmful. 
 This could probably be taken care of by setting the group name to the same 
name on both.

If I get any additional information I will post my findings.

Thank you all,
Ricardo J. Parada





> On Mar 21, 2022, at 11:28 AM, Steve Peery <spe...@icloud.com> wrote:
> 
> I’ve also been using it for years to synchronize instances.
> 
> I’m not sure it is going to do what you want. You say you want to use it so 
> you can update "without resorting to fetching”. I think the synchronization 
> notifications simply pass the global IDs of the objects that have changed so 
> they are refetched in the receiving instances.
> 
> Steve
> 
> 
> 
>> On Mar 20, 2022, at 6:21 PM, Paul Hoadley via Webobjects-dev 
>> <webobjects-dev@lists.apple.com <mailto:webobjects-dev@lists.apple.com>> 
>> wrote:
>> 
>> Hi Ricardo,
>> 
>> On 19 Mar 2022, at 14:25, Ricardo Parada via Webobjects-dev 
>> <webobjects-dev@lists.apple.com <mailto:webobjects-dev@lists.apple.com>> 
>> wrote:
>> 
>>> Does anybody use ERJGroupsSynchronizer?
>> 
>> We've been using it for years now, albeit with some light modifications to 
>> allow JGroups to work on AWS (originally via the Meltmedia AWS_PING project, 
>> but now via our own fork of that since it's essentially abandonware).
>> 
>>> I’m trying to synchronize two EOF stacks within a single VM. I don’t want 
>>> the synchronization to happen across application instances. 
>>> 
>>> The video from Mike Shrag from a WOWODC conference said it can be single VM 
>>> or across VM. I’m interested in the single VM but have not yet figured out 
>>> how to do it. 
>>> 
>>> Basically, I have a background task doing work on a separate EOF stack and 
>>> I want the changes to reflect on the EOF stack used by the user interface 
>>> without resorting to fetching. 
>> 
>> Intra-JVM like that is not a configuration we've used. Can you walk us 
>> through what you've tried and why you think it's not working? There have 
>> been a few others using it over the years, maybe they're still on the list.
>> 
>> 
>> -- 
>> Paul Hoadley
>> https://logicsquad.net/ <https://logicsquad.net/>
>> https://www.linkedin.com/company/logic-squad/ 
>> <https://www.linkedin.com/company/logic-squad/>
>> 
>> _______________________________________________
>> Do not post admin requests to the list. They will be ignored.
>> Webobjects-dev mailing list      (Webobjects-dev@lists.apple.com 
>> <mailto:Webobjects-dev@lists.apple.com>)
>> Help/Unsubscribe/Update your Subscription:
>> https://lists.apple.com/mailman/options/webobjects-dev/speery%40me.com 
>> <https://lists.apple.com/mailman/options/webobjects-dev/speery%40me.com>
>> 
>> This email sent to spe...@me.com <mailto:spe...@me.com>
 _______________________________________________
Do not post admin requests to the list. They will be ignored.
Webobjects-dev mailing list      (Webobjects-dev@lists.apple.com)
Help/Unsubscribe/Update your Subscription:
https://lists.apple.com/mailman/options/webobjects-dev/archive%40mail-archive.com

This email sent to arch...@mail-archive.com

Reply via email to