[Freeipa-users] ns-slapd using all CPU ressources

[Rob Crittenden]

Domingues Luis Filipe wrote:
> Hi all,
> 
> On our infra, we have two machines running Fedora with FreeIPA installed.
> 
> we have an issue with ns-slapd using 100% of CPU after a while. If we
> restart the service, it starts to use all CPU resources after one day.
> 
> Outpute of the command strace -c -p <ns-slapd PID> running for 4 minutes is:
> 
> % time     seconds  usecs/call     calls    errors syscall
> ------ ----------- ----------- --------- --------- ----------------
>  99.80  229.603633       11247     20415           poll
>   0.15    0.340032          10     32983         4 futex
>   0.05    0.114068      114068         1           restart_syscall
>   0.00    0.003464           0     20420     20416 getpeername
>   0.00    0.002752           0     20416           clock_gettime
>   0.00    0.001920           0      9840           read
>   0.00    0.000205           5        45           close
>   0.00    0.000036           2        22           access
>   0.00    0.000017           1        22           open
>   0.00    0.000016           1        24           accept
>   0.00    0.000012           0        45           setsockopt
>   0.00    0.000007           0        22           fstat
>   0.00    0.000000           0        22           stat
>   0.00    0.000000           0         1           sendto
>   0.00    0.000000           0        24           getsockname
>   0.00    0.000000           0         4           getsockopt
>   0.00    0.000000           0        70           fcntl
>   0.00    0.000000           0        22           gettimeofday
> ------ ----------- ----------- --------- --------- ----------------
> 100.00  230.066162                104398     20420 total
> 
> 
> 
> Plus we looked at the syscalls using FTrace:
> 
> ns-slapd-7963  [000] .... 4063846.395630: sys_sched_yield()
> ns-slapd-7956  [000] .... 4063846.395631: sys_sched_yield -> 0x0
> ns-slapd-7956  [000] .... 4063846.395632: sys_sched_yield()
> ns-slapd-7973  [000] .... 4063846.395633: sys_sched_yield -> 0x0
> ns-slapd-7973  [000] .... 4063846.395634: sys_sched_yield()
> ns-slapd-7965  [000] .... 4063846.395635: sys_sched_yield -> 0x0
> ns-slapd-7965  [000] .... 4063846.395637: sys_sched_yield()
> ns-slapd-7963  [000] .... 4063846.395637: sys_sched_yield -> 0x0
> ns-slapd-7963  [000] .... 4063846.395639: sys_sched_yield()
> ns-slapd-7956  [000] .... 4063846.395640: sys_sched_yield -> 0x0
> ns-slapd-7956  [000] .... 4063846.395641: sys_sched_yield()
> ns-slapd-7973  [000] .... 4063846.395642: sys_sched_yield -> 0x0
> ns-slapd-7973  [000] .... 4063846.395643: sys_sched_yield()
> ns-slapd-7965  [000] .... 4063846.395644: sys_sched_yield -> 0x0
> 
> The sys_sched_yield function is called almost every 2 microseconds. It seems too much.

Your best bet is to get a pstack or full backtrace to see what 389-ds is
doing. See
http://directory.fedoraproject.org/docs/389ds/FAQ/faq.html#debugging-hangs

rob