Matt thank you for your reply, Indeed I saw your question too yesterday. In regards to points 3-4 of my question I suppose that as you mention, if one shuts down gracefully the client node and if the number of threads responsible for rebalancing the data gets tweaked, then I guess the amount of time the cluster blocks could be managed. For point 2 I think it’s necessary for someone from the dev team to provide a bit more insight as to what ignite’s behavior is in regards to client nodes joining/leaving the cluster as I fail to understand why PEM is triggered for such nodes given their natural exclusion from computations and the lack of storage of cache data in them. Indeed if the case is that PEM is triggered for client nodes when joining/leaving, scenarios where remote clients come and go on demand become difficult to accommodate at best, and this sounds very restrictive. I simply need to know more on this otherwise it would not be possible to develop a working strategy for accommodating clients that come, do a bit of work, and then they leave until next time.
Kind regards Dr. Evangelos Morakis Software Architect > On 24 Apr 2019, at 21:21, MattNohelty <[email protected]> wrote: > > I have these same questions and posted about this yesterday > (http://apache-ignite-users.70518.x6.nabble.com/What-happens-when-a-client-gets-disconnected-td27959.html). > > Based on my understanding: > > 1) Yes, PME will always happen when a server node joins > > 2) This is my biggest question. I'm currently using 2.4 and it appears PME > is happening when a client connects or disconnects but I received one > response that seemed to indicate that PME should not happen in this case in > the newest versions of Ignite. I agree with your reasoning that these > rebalancing processes do not seem necessary as all the data is on the server > nodes which is what prompted my initial question. > > 3) The responses I received do say that the cluster blocks while this > happens and I've seen evidence of this as well. I've only seen substantial > blocking though when a client node is disconnected ungracefully. When the > start or stop properly, we do not observe substantial blocking on the other > clients. > > This behavior has caused some issues for us recently and it seems very > problematic that one client node crashing can cause issues on all other > client nodes. Granted, we are still on Ignite 2.4 so maybe this has been > correct in 2.7, but I would really like to understand what the expected > behavior should be. > > > > -- > Sent from: http://apache-ignite-users.70518.x6.nabble.com/
