[syslog-ng] syslog-ng consumes a lot of cpu

[C. L. Martinez]

On Tue, Jun 4, 2013 at 12:25 PM, C. L. Martinez <carlopmart at gmail.com> wrote:
> On Tue, Jun 4, 2013 at 11:18 AM, C. L. Martinez <carlopmart at gmail.com> wrote:
>> HI all,
>>
>>  I have installed syslog-ng 3.3.8 under an OpenBSD with a simple configuration:
>>
>> @version: 3.3
>>
>> options {
>>         log_fifo_size(30000);
>>         use_dns (no);
>>         use_fqdn (no);
>>         keep_hostname (yes);
>> };
>>
>>
>> # Define what files to be monitored
>> source s_network {
>>         tcp(port(10514) flags(no-multi-line));
>> };
>>
>>
>> # Define filters
>>
>>
>>
>> # Define default destinations
>> destination d_ossec_fifo {
>>         pipe("/var/log/syslog.fifo");
>> };
>>
>>
>> #
>> # Default log actions
>> #
>>
>> log {
>>         source(s_network);
>>         log { destination(d_ossec_fifo); flags(flow-control,final); };
>> };
>>
>> but it is consuming a lot of CPU:
>>
>> load averages:  1.13,  1.09,  1.08
>>
>>                       obsdhost 11:17:49
>> 25 processes: 1 running, 23 idle, 1 on processor
>> CPU states:  0.8% user,  0.0% nice,  3.5% system,  0.0% interrupt, 95.7% idle
>> Memory: Real: 29M/356M act/tot Free: 2655M Cache: 297M Swap: 0K/3067M
>>
>>   PID USERNAME PRI NICE  SIZE   RES STATE     WAIT      TIME    CPU COMMAND
>> 30813 root      64    0 1260K 4204K run       -        60:49 99.02% syslog-ng
>>
>> Any idea why??
>
> Changing destination to a file instead of a pipe, all works as expected:
>
> load averages:  0.16,  0.87,  1.25
> 25 processes: 24 idle, 1 on processor
> CPU states:  0.0% user,  0.0% nice,  0.4% system,  0.0% interrupt, 99.6% idle
> Memory: Real: 29M/363M act/tot Free: 2649M Cache: 304M Swap: 0K/3067M
>
>   PID USERNAME PRI NICE  SIZE   RES STATE     WAIT      TIME    CPU COMMAND
> 11308 root       2    0 1440K 3712K sleep     kqread    0:01  0.05% syslog-ng

Where can be the problem when pipe is used??