NetBSD8.1: syslogd spinning, kqueue and klog?

[Paul Ripke <stix%stix.id.au@localhost>]

I look at my machine today, and syslogd is burning a core, mostly in system
time. ktruss sees it spinning thusly:

   261      1 syslogd  0.000001183 __kevent50(0x6, 0x733392139000, 0, 0x733392142000, 0x40, 0x7f7fffba0960) = 1
   261      1 syslogd  0.000000900 __clock_gettime50(0x3, 0x7f7fffba0950) = 0
   261      1 syslogd  0.000001146 read(0x4, 0x73339212afe0, 0) = 0
       ""
   261      1 syslogd  0.000001140 __kevent50(0x6, 0x733392139000, 0, 0x733392142000, 0x40, 0x7f7fffba0960) = 1
   261      1 syslogd  0.000000929 __clock_gettime50(0x3, 0x7f7fffba0950) = 0
   261      1 syslogd  0.000001135 read(0x4, 0x73339212afe0, 0) = 0
       ""
   261      1 syslogd  0.000001176 __kevent50(0x6, 0x733392139000, 0, 0x733392142000, 0x40, 0x7f7fffba0960) = 1
   261      1 syslogd  0.000000906 __clock_gettime50(0x3, 0x7f7fffba0950) = 0
   261      1 syslogd  0.000001195 read(0x4, 0x73339212afe0, 0) = 0
       ""

fd 4 is klog, and indeed, there's supposedly a pending event on kqueue:

USER     CMD          PID   FD MOUNT       INUM MODE         SZ|DV R/W
root     syslogd      261 root  /               2 drwxr-xr-x    1024 r 
root     syslogd      261   wd  /               2 drwxr-xr-x    1024 r 
root     syslogd      261    0  /           21204 crw-rw-rw-    null rw
root     syslogd      261    1  /           21204 crw-rw-rw-    null rw
root     syslogd      261    2  /           21204 crw-rw-rw-    null rw
root     syslogd      261    3* unix dgram  <-> /var/run/log [creat]
root     syslogd      261    4  /           21206 crw-------    klog r 
root     syslogd      261    5  /var           19 -rw-r--r--       4 w 
root     syslogd      261    6* kqueue pending 1
root     syslogd      261    7* internet6 dgram udp *:syslog
root     syslogd      261    8  /var       106001 -rw-r--r--  668848 w 
root     syslogd      261    9  /var       106001 -rw-r--r--  668848 w 
root     syslogd      261   10  /var       106013 -rw-------  153874 w
...

Known-already-fixed issue, or new? Merely restarting syslogd "fixed"
the issue, fwiw.

NetBSD slave 8.1_STABLE NetBSD 8.1_STABLE (SLAVE) #5: Wed Aug 28 23:37:45 AEST 2019  stix@slave:/home/netbsd/netbsd-8/obj.amd64/home/netbsd/netbsd-8/src/sys/arch/amd64/compile/SLAVE amd64

--
Paul Ripke
"Great minds discuss ideas, average minds discuss events, small minds
 discuss people."
-- Disputed: Often attributed to Eleanor Roosevelt. 1948.