> > Under heavy client load, the log shows many "deferring operation: binding" > > messages in the same second. slapd is using only 400% cpu (of 1600 > > possible). > > Probably you could increase # of listeners. In a pure Bind-only workload > slapd ought to be able to utilize 100% of all cores.
Do you mean the tcp port listeners on the slapd process? Do you think I'm hitting a socket accept queue max backlog or something else? slapd -h ldap://:389 ldaps://:636 On Tue, Apr 13, 2021 at 1:32 PM Howard Chu <[email protected]> wrote: > > Zetan Drableg wrote: > > openldap 2.4.57 on 16 core OracleLinux VMs with NVME disk. > > 8 nodes in n-way multi master configuration, MDB backend, 50k unique DNs. > > We see about 10,000 auths per minute per node. > > > > Under heavy client load, the log shows many "deferring operation: binding" > > messages in the same second. slapd is using only 400% cpu (of 1600 > > possible). > > Probably you could increase # of listeners. In a pure Bind-only workload > slapd ought to be able to utilize 100% of all cores. > > > > [2021-04-13 19:15:58] connection_input: conn=150474 deferring operation: > > binding > > > > When I write LDIFs to one node like delete user or remove user from group, > > we see spikes in authentication latency metrics (what's normally .2 - .5 > > second > > response time goes up to 15-30 seconds) across all nodes in the cluster at > > the same time. > > > > What knobs can be adjusted to allow for more concurrency? It seems like > > writes are impacting reads. > > You need more information, like I/O wait %, network % utilization, to > identify the cause of these latency spikes. > > Nobody can suggest what to tune without knowing why the bottleneck occurs. > > -- > -- Howard Chu > CTO, Symas Corp. http://www.symas.com > Director, Highland Sun http://highlandsun.com/hyc/ > Chief Architect, OpenLDAP http://www.openldap.org/project/
