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Cycling the Management Kernel

Tom_Davidson

VIP Member
Is it safe to cycle the E1 Management kernel? By cycle, I mean 'kill', most kernels respawn if they go down, I'm not sure this one does.

I'm asking because it has been running since Feb 10, and in my ignorance, I set a max size of CPU Usage in one of my tools to 99999 seconds. I will reach that soon.

If you know it does or doesn't would you please let me know.

And yes I realize this is a 'lazy' way of handling the issue. :D

Tom
E8.12, Tools 8.98.4.4, IBM i V6R1
 

altquark

Legendary Poster
I tried this on my test installation by killing the kernel and waiting a little while to see if it respawned. It did not. Likely as not, its not one that automatically respawns !
 

altquark

Legendary Poster
The "right" thing to do, of course, is to arrange for once a week or once a month downtime - just to cycle services. Its a good thing that JDE stays up for that amount of time, but its still wise to bounce every now and then.

By the way, killing the management kernel only stops the Server Manager getting the runtime information - ie, processes and zombies - it certainly doesn't stop JDE from working.
 

Tom_Davidson

VIP Member
Jon,

When it comes to bouncing the "right" thing varies. We do try to bounce 3 times a year. Ever since Oracle introduced Call Object recycling, I've found my need to bounce has been greatly reduced.

I know I can kill a misbehaving a UBE kernel, and it will respawn. Now if Oracle would only give us the option of recycling a failing Metadata kernel, sometimes killing it works, and sometimes it bring JDE down <sigh>, 99% of the reasons I cycle would be gone.

I do recycle the OAS and WebLogic JAS instances much more often. But since I have multiple ones of those it isn't a big deal.

Tom
 

altquark

Legendary Poster
I know I can kill a misbehaving a UBE kernel, and it will respawn. Now if Oracle would only give us the option of recycling a failing Metadata kernel, sometimes killing it works, and sometimes it bring JDE down <sigh>, 99% of the reasons I cycle would be gone.
I believe recycling the metadata kernel became a lot more stable since 9.1.5.2 - certainly if I recycle my metadata kernel, it respawns almost immediately. We discovered a LOT of the significant issues with Metadata Kernels with 9.1.4x tools release at my last customer, and how important it was to have the metadata kernels correctly tuned. I'd also expect more effort to go into the next couple of tools releases as far as scalability and tuning of the metadata kernels.
 

Tom_Davidson

VIP Member
That's good news Jon.

I have permission to go to 9.1.5 this fall, in our 9.1 instance, we have too many go-lives this summer.

I'm working on getting permission to go to 9.1.x in 8.12 but they are pushing back on the user interface changes. They know they have to go sometime, but inertia you know.

Tom
 
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