Re: NFS lockup after UDP fragments getting lost (was: 8.1 tstile lockup after nfs send error 51)

[maya%NetBSD.org@localhost]

On Wed, Jul 31, 2019 at 11:42:26AM -0500, Don Lee wrote:
> If you go back a few years, you can find a thread where I reported tstile lockups on PPC. I don’t remember the details, but it was back in 6.1 as I recall. This is not a new problem, and not limited to NFS. I still have a similar problem with my 7.2 system, usually triggered when I do backups (dump/restore). The dump operation locks up and cannot be killed. The system continues, except any process that trips over the tstile also locks up. Eventually, the system grinds to a complete halt. (can’t even log in) If I catch it before that point, I can almost reboot, but I have to power cycle to kill the tstile process(es), or the reboot also hangs.

It's worth reminding that -o tcp is an option.