Forum Discussion

NiHo_202842's avatar
NiHo_202842
Icon for Cirrostratus rankCirrostratus
Mar 07, 2017

alertd high cpu usage

Hello,

So we tried taxing the HSL logging of our 12.1.2 cluster with several (4) simple

while true; do curl http://virtual-ip/; done
curl loops. The virtual IP had a simple iRule that logged
[HTTP::request]
several times. Our logging is BSD syslog to HSL, to a logstash pool.

During our testing, we saw alertd rising to 100% CPU and maxing out there. CPU usage on the dashboard increased aswell, as you see in the image below.

sys log-config destination remote-high-speed-log elk-hsl-destination {
    pool-name syslog-pool
}
sys log-config destination remote-syslog rsyslog-to-hsl-elk {
    remote-high-speed-log elk-hsl-destination
}
sys log-config filter elk-hsl-filter {
    level info
    publisher elk-hsl-publisher
}
sys log-config publisher elk-hsl-publisher {
    destinations {
        rsyslog-to-hsl-elk { }
    }
}

Any idea how we can combat this? We would like to use HSL to reduce CPU consumption, but this seems like a lot of fuss for simple logging. Ideas? Thanks!