Рубрики
k8s Linux Performance tests storage

fio (IOPS test)

Original topic can be accessed by https://www.ibm.com/cloud/blog/using-fio-to-tell-whether-your-storage-is-fast-enough-for-etcd


Test IOPS in Linux system.

tar -xzf fio.tgz
yum localinstall *.rpm
cd /data0/etcd
mkdir test-data;fio —rw=write —ioengine=sync —fdatasync=1 —directory=test-data —size=22m —bs=2300 —name=mytest

#!/bin/bash
now=$(date "+%Y%d%m-%H%M");
while true;
do
fio --rw=write --ioengine=sync --fdatasync=1 --directory=/data0/etcd/test-data --size=22m --bs=2300 --name=${now}_mytest >> /data0/etcd/results.log;
sleep 600;
done
Рубрики
k8s Linux screen

screen

Start command in a detached screen with logging to file, example captures pod logs in the background:

screen -dmS screen_name bash -c 'kubectl logs -f pod_name | tee /home/user/log.txt';

Close all detached screens:
screen -ls | grep ‘(Detached)’ | awk ‘sys {screen -S $1 -X quit}’

Рубрики
k8s

K8S

Sort pods by creation time:
kubectl get pods --sort-by=.metadata.creationTimestamp


Enable kubelet to log level 5:
sed -i -e 's/--v=1/--v=5/g' /etc/systemd/system/kubelet.service; systemctl daemon-reload; systemctl restart kubelet

Check pod-eviction-timeout:
grep pod-eviction-timeout /etc/kubernetes/manifests/kube-controller-manager.yml

Change pod-eviction-timeout:
sed -i 's/- --pod-eviction-timeout=120s/- --pod-eviction-timeout=5m/g' /etc/kubernetes/manifests/kube-controller-manager.yml

Get pod information in yaml format:
kubectl get pod POD_NAME -o yaml