file system deadlock - the whole story?

[User Freebsd]

On Wed, 19 Jul 2006, Robert Watson wrote:

>
> On Wed, 19 Jul 2006, User Freebsd wrote:
>
>> Also note that under FreeBSD 4.x, all three of these machines were pretty 
>> much my more solid machines, with even more vServers running on them then 
>> I'm able to run with 6.x ... once I got rid of using unionfs, stability 
>> skyrocketed :(
>> 
>> Hrmmmm ... but, your 'controller driver' comment ... that is one common 
>> thing amongst all three servers ... they are all running the iir driver ... 
>> not sure the *exact* controller, but pluto (older Dual-PIII) shows it as:
>
> Yes, this was going to be my next question -- if you're seeing wedges under 
> load and there's a common controller in use, maybe we're looking at a driver 
> bug.  Bugs of those sort typically look a lot like what you describe: an I/O 
> is "lost" and so eveything that depends on the I/O wedges waiting for it, 
> leading to a lot of processes hanging around waiting for vnode locks, etc.

'k, but how do we debug *that*? :(  If it was one, I'd suspect hardware 
... but *three*, and only acting up *after* upgrading to FreeBSD 6.x, and 
only acting up under load ...

----
Marc G. Fournier           Hub.Org Networking Services (http://www.hub.org)
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