Jazz Forum Welcome to the Jazz Community Forum Connect and collaborate with IBM Engineering experts and users

SiBUS sync and its impact on RAM running in clustered enviro

Hi Team,

We would like to know the impact of WAS SiBUS synchronization (breaking quite often) in RAM clustered environment.

We tested and found that ASSET UPLOAD/DELETE does not have any known impact (when tested across 2 JVM's) in the absence of the SiBUS sync.

Please help!

Thanks/Regards
Avnindra

0 votes



2 answers

Permanent link
In the absence of SiBUS sync, we made changes to user ROLES (on one JVM instance), and confirmed seen the changes reflect on another JVM instance running (o fRAM clustered environment)


Hi Team,

We would like to know the impact of WAS SiBUS synchronization (breaking quite often) in RAM clustered environment.

We tested and found that ASSET UPLOAD/DELETE does not have any known impact (when tested across 2 JVM's) in the absence of the SiBUS sync.

Please help!

Thanks/Regards
Avnindra

0 votes


Permanent link
The problem is that when they don't talk to each other that certain data can remain stale. Especially roles.

I have seen on some systems that the bus will fail and then a few seconds later it works fine. In the latest 7202 testfix and in 7502 and later when this condition has been detected the server will clear its caches. This way it will then sync up with the database instead of using in-memory cache.

Consistent failure is a different problem. In those cases other servers won't see changes to roles such as those assigned to All users because those are kept permanent in an in-memory cache. If it never sees a clear cache request it doesn't change.

Just looking at a role is not using any cache information so that is always going against the database. What is cached is the roles within logged in users. You could change the role and if the bus is not working the logged in users on another server in the cluster would not see the change and they would still have the older entitlements.

So intermittent short term failures are very tolerable. What is not tolerable is a long term failure.

0 votes

Your answer

Register or log in to post your answer.

Dashboards and work items are no longer publicly available, so some links may be invalid. We now provide similar information through other means. Learn more here.

Search context
Follow this question

By Email: 

Once you sign in you will be able to subscribe for any updates here.

By RSS:

Answers
Answers and Comments
Question details

Question asked: Mar 09 '12, 9:17 a.m.

Question was seen: 3,795 times

Last updated: Mar 09 '12, 9:17 a.m.

Confirmation Cancel Confirm