I had a similar sounding issue, although not in a Kube cluster. Nifi was running in a docker container and the issue was the log rotation interacting with the log file being mounted from the host. The mounted log file was not deleted on rotation, meaning that once rotation was triggered by log file size it would be continually triggered because the new log file was never emptied. The clue was that the content of rotated logfiles was mostly the same, with only a small number of messages appended to each new one. Rotating multi GB logs was enough to destroy performance, especially if it was being triggered frequently by debug messages.
On Thu, Jan 11, 2024 at 7:14 AM Aaron Rich <[email protected]> wrote: > Hi Joe, > > It's a pretty fixed size objects at a fixed interval- One 5mb-ish file, we > break down to individual rows. > > I went so far as to create a "stress test" where I have a generateFlow( > creating a fix, 100k fille, in batches of 1000, every .1s) feeding right > into a putFile. I wanted to see the sustained max. It was very stable, fast > for over a week running - but now it's extremely slow. That was able as > simple of a data flow I could think of to hit all the different resources > (CPU, memory > > I was thinking too, maybe it was memory but it's slow right at the start > when starting NiFi. I would expect the memory to cause it to be slower over > time, and the stress test showed it wasn't something that was fluenting > over time. > > I'm happy to make other flows that anyone can suggest to help > troubleshoot, diagnose issue. > > Lars, > > We haven't changed it between when performance was good and now when it's > slow. That is what is throwing me - nothing changed from NiFi configuration > standby. > My guess is we are having some throttling/resource contention from our > provider but I can't determine what/where/how. The Grafana cluster > dashboards I have don't indicate issues. If there are suggestions for > specific cluster metrics to plot/dashboards to use, I'm happy to build them > and contribute them back (I do have a dashboard I need to figure out how to > share for creating the "status history" plots in Grafana). > The repos aren't full and I tried even blowing them away just to see if > that made a difference. > I'm not seeing anything new in the logs that indicate an issue...but maybe > I'm missing it so I will try to look again > > By chance, are there any low level debugging metrics/observability/etc > that would show how long things like writing to the repository disks is > taking? There is a part of me that feels this could be a Disk I/O resource > issue but I don't know how I can verify that is/isn't the issue. > > Thank you all for the help and suggestions - please keep them coming as > I'm grasping at straws right now. > > -Aaron > > > On Wed, Jan 10, 2024 at 10:10 AM Joe Witt <[email protected]> wrote: > >> Aaron, >> >> The usual suspects are memory consumption leading to high GC leading to >> lower performance over time, or back pressure in the flow, etc.. But your >> description does not really fit either exactly. Does your flow see a mix >> of large objects and smaller objects? >> >> Thanks >> >> On Wed, Jan 10, 2024 at 10:07 AM Aaron Rich <[email protected]> wrote: >> >>> Hi all, >>> >>> >>> >>> I’m running into an odd issue and hoping someone can point me in the >>> right direction. >>> >>> >>> >>> I have NiFi 1.19 deployed in a Kube cluster with all the repositories >>> volume mounted out. It was processing great with processors like >>> UpdateAttribute sending through 15K/5m PutFile sending through 3K/5m. >>> >>> >>> >>> With nothing changing in the deployment, the performance has dropped to >>> UpdateAttribute doing 350/5m and Putfile to 200/5m. >>> >>> >>> >>> I’m trying to determine what resource is suddenly dropping our >>> performance like this. I don’t see anything on the Kube monitoring that >>> stands out and I have restarted, cleaned repos, changed nodes but nothing >>> is helping. >>> >>> >>> >>> I was hoping there is something from the NiFi POV that can help identify >>> the limiting resource. I'm not sure if there is additional >>> diagnostic/debug/etc information available beyond the node status graphs. >>> >>> >>> >>> Any help would be greatly appreciated. >>> >>> >>> >>> Thanks. >>> >>> >>> >>> -Aaron >>> >>
