Having not seen the dreaded turnstile issue in ages, a NetBSD-9.99.99/amd64
got stuck on shutdown last night with:
db{0}> ps
PID LID S CPU FLAGS STRUCT LWP * NAME WAIT
4761 4761 3 0 0 ffff83a478576940 sync tstile
5499 5499 3 1 40 ffff83a486cb2740 halt tstile
5262 5262 3 0 180 ffff83a4862ecac0 pickup kqueue
4060 4060 3 0 40 ffff83a486cb2300 halt tstile
...
Today's very unusual use pattern was that I created several 5GB
files in its large tmpfs /tmp and then moved them to a ZFS partition.
As I recollect, I then did a git log in github/netbsd/src, and nothing
happened. top showed pagedaemon at 100%. ^C in the git xterm eventually
returned, so no more git process.
>From memory, doing a bt/a on pgdaemon's *lwp just showed
uvm_pageout
uvm_availmem
Things carried on for a while, and a subsequent git log worked, but
then mutt got stuck in tstile. AFAIR it was the only process in
tstile. I then shutdown -p now. Wondered why not much was happening.
Repeated the shutdown in the same xterm which was still responsive.
ddb then showed me the above. Evenutally I hit the power-off switch.
So for me, no PUFFS was involved, but git, tmpfs, ZFS were.
Cheers,
Patrick
