All, I wanted to provide an update. The issue went away when  the production workload moved off the Unity but were still using the server, switches, and different storage.  The above was key in reducing the number of components that could be introduction the problem. With the above information we focused on the connections between the 5596UP switch and the Unity. One at a time we disabled switch ports and waited to see if the issue continued or stopped. The above took some time, figures we did not find anything until we got to the last port on SPA. When disabled, the issue stopped.   Fiber patch cables were cleaned and re-seated and the port was turned back on. We continue to monitor, without the production load the issue has become more intermittent, I will know more by end of the week.   So far the cleaning and re-seating of the fiber looks like it might have fixed the issue.  I will update again after we have run a week without issue.
Hello all  UNITY flash users. I wanted to check with the user base if anyone else has seen performance issues after going to code 4.3.1.1525703027? A Dell technical advisory came out that applied to the drives in my Unity 400F, so I upgraded to 4.3.1.1525703027. The previous code I was running did not have a performance issue code, 4.3.0.1522077968.  Latency immediately jumped on all esxhost datastores after the code update. I do have a SR open 11153806. on the left of the graph when it was flat was before code update. On the right with the spikes is after the code update. If you do not have any monitoring tools, the below is also indicated something changed. No Esxhost disk heart beat timeouts before code update. After code update, Esxhost host disk heart beats now regularly timeout, which  was not happening before the code update.  I was wondering if anyone else is running 4.3.1.1525703027 ?   Has anyone else see performance issues after upgrading to  4.3.1.1525703027? I have a single traditional pool configured , which does include the vault drives. Compression is turned on. The below graph is from a monitoring product we use. The key is it really shows the change from before the code update and after the code update finished at around 8:00 am.    [IMAGE]    I also want to know if anyone is seeing periodic drive queue length spikes? To the best of my knowledge the drive queue length spike was not caused by a change in work load and it lasted 3-5 min. I was wondering if an internal process on the unity will cause the below? The graph is of the first 10 drives in DPE. [IMAGE]  All, thank you, 
Unity 400F code 4.3.1.1525703027 and performance issues