trouble with "error: event_add failed. in cpsl."

Hello,

unbound-1.9.1 with moderate load 1k queries/s peak

after restart everything works fine but after some ours the log is flooded wthis way:

2019-05-24 15:49:53.874400500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.888628500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.892736500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:53.892789500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.900451500 [1558705793] unbound[33794:0] error: event_add failed. in cpsl.
2019-05-24 15:49:53.902052500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.907473500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.924918500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:53.926381500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:53.929426500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:53.936023500 [1558705793] unbound[33794:1] error: event_add failed. in cpsl.
2019-05-24 15:49:53.943565500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:53.950292500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.954694500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.957886500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.971253500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:53.976480500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:53.981105500 [1558705793] unbound[33794:0] error: event_add failed. in cpsl.
2019-05-24 15:49:53.986870500 [1558705793] unbound[33794:1] error: event_add failed. in cpsl.
2019-05-24 15:49:53.998374500 [1558705793] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:54.004480500 [1558705794] unbound[33794:7] error: event_add failed. in cpsl.
2019-05-24 15:49:54.007178500 [1558705794] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:54.009645500 [1558705794] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:54.023203500 [1558705794] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:54.037888500 [1558705794] unbound[33794:1] error: event_add failed. in cpsl.
2019-05-24 15:49:54.044780500 [1558705794] unbound[33794:7] error: event_add failed. in cpsl.

which parameter are suggested to check / modify?

this are the none zone related configuration entries:
  aggressive-nsec: yes
  chroot: "/chroot/unbound"
  do-daemonize: no
  extended-statistics: yes
  logfile: ""
  log-replies: yes
  log-tag-queryreply: yes
  harden-referral-path: yes
  harden-glue: yes
  outgoing-tcp-mss: 1220
  pidfile: ""
  prefetch-key: yes
  rrset-roundrobin: yes
  tcp-mss: 1220
  serve-expired: yes
  serve-expired-ttl-reset: yes
  statistics-interval: 3600
  statistics-cumulative: yes
  unwanted-reply-threshold: 10000
  val-log-level: 2
  auto-trust-anchor-file: root-rfc5011
  num-threads: 8
  outgoing-range: 10000
  msg-cache-size: 1g
  msg-cache-slabs: 8
  rrset-cache-size: 1g
  rrset-cache-slabs: 8
  infra-cache-numhosts: 65536
  infra-cache-slabs: 8
  key-cache-size: 1g
  key-cache-slabs: 8
  neg-cache-size: 1g
  num-queries-per-thread: 4096
  ratelimit-slabs: 8
  ip-ratelimit-slabs: 8
  do-ip6: no
  prefetch: no

Andreas

These messages continue even if no new requests arrive.

After downgrade to 1.8.1 with an unchanged configuration file the problem went away.
I'll give 1.9.2 a try once it's available.

Andreas

A. Schulze via Unbound-users:

unbound-1.9.1 with moderate load 1k queries/s peak

after restart everything works fine but after some ours the log is flooded wthis way:

2019-05-24 15:49:53.874400500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.
2019-05-24 15:49:53.888628500 [1558705793] unbound[33794:3] error: event_add failed. in cpsl.

These messages continue even if no new requests arrive.

After downgrade to 1.8.1 with an unchanged configuration file the problem went away.
I'll give 1.9.2 a try once it's available.

I replaced 1.8.1 (known to work) with 1.9.2~rc3 on one server that "run crazy" with 1.9.1,
At least over 3 days I did not noticed the log message mentioned in $subject - fine.

There are numerous changes between 1.8.1/utils/netevent.c, 1.9.1/utils/netevent.c
(that may introduce the failure I saw) and 1.9.2/utils/netevent.c
(that may solve the issue again)
Does this sound reasonable?

Andreas

I’m also seeing the same errors flooding logs on my busiest server also running 1.9.1.

In your case were the error messages immediately preceeded by “error: could not event_del on close”?

-- 

Clay Cooper

Information and Technology Services
Finance & Administration
Rochester Institute of Technology

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with 1.9.2 it never happened again

Andreas