kernel_task goes haywire on a write operation

wazungu · partially protected Joined: 01 Apr 2009 Posts: 6

When I write to a mounted XRAID (via FC), my kernel_task process goes haywire, maxes one of my cores at 100%, and locks the app that wrote to it (usually FCP).

Does that sound like a hardware issue (a FC card, perhaps)? Or, a software issue? Trying to diagnose, any help is appreciated - thanks!

dbaylon · JBOD Joined: 11 Sep 2009 Posts: 3

Hi,

what kind of Mac are you using? maybe is to small or could be hardware problem if you have another computer with the same model try to isolate the problem replacing known good parts for the others.

wazungu · partially protected Joined: 01 Apr 2009 Posts: 6

thorpej · fully protected Joined: 25 Aug 2009 Posts: 10

wazungu · partially protected Joined: 01 Apr 2009 Posts: 6

You're right, thorpej - it's been intermittent and hard to diagnose.

I have an Xserve (metadata master), two Macs all connected with Fibre Channel. I'm using MetaSAN for the SAN software. Sometimes when I try to write to the SAN, the kernel_task goes crazy, locks up the app and pegs a CPU core.

I'm writing to it right now with an MP4 encoding app, and it's working fine. Large file copies cause it to hang also.

Could that be an FC card issue, if larger transfers cause it to hang? Encoding video to a drive is more like a constant dribble of data - very low.

I know you're all XSAN guys (I may be joining you soon), but wanted to ask here as it's one of the best SAN resources out there. I'm exploring the SAN software angle with that vendor, and wanted to see if you'd seen hardware problems like this with XSAN setups (because at the end of the day, they both do the same thing over the same kinds of equipment).

Thanks!