Re: TSTILE lockups on disk dump/backups

On Sat, Dec 21, 2024 at 02:20:23AM -0600, Don Lee wrote:
> Any thought about how I should deal with this? My kernel debugging
> skills are weak. Is there anything I can do to produce useful debug
> information next time this happens?

A tstile just means the process/kernel thread is blocked for a longer
time waiting for "something". In this context that would typically be
either a disk buffer ("buf") read from disk (the source you are backing
up) or a network buffer ("mbuf") handed to the network device output
queue.

This would point to a bug in the disk driver or the network driver.

The other option would be your system runing out of kernel address space,
so it can not allocate either type of buffer. This would show up in 
the output of vmstat -s (or you are running against limits for either
type of buffer, but I would expect that to fail differently).

Can you start new processes in the state when it hangs? Like the vmstat -s 
mentioned above, or "crash" to look at kernel state? I am not sure "crash"
would work on macppc and 9.x good enough.

Martin