chenk008

You can demostrate how kubernetes stores everything in etcd (v3):

One-liner

You can exec etcdctl rigth in the etc pod:

kubectl exec -it \
  -n kube-system etcd-minikube \
  -- sh -c 'ETCDCTL_CACERT=/var/lib/localkube/certs/etcd/ca.crt \
 ETCDCTL_CERT=/var/lib/localkube/certs/etcd/peer.crt \

Overly aggressive CFS

We're looking at CPU bandwidth control via CFS:

https://www.kernel.org/doc/Documentation/scheduler/sched-bwc.txt

Reproduction program

Program does number of iterations, in each iteration we burn CPU in small chunks until we get 5ms of real time spent. On each iteration we also print how much

Common Options

-#, --progress-bar Make curl display a simple progress bar instead of the more informational standard meter.

-b, --cookie <name=data> Supply cookie with request. If no =, then specifies the cookie file to use (see -c).

-c, --cookie-jar <file name> File to save response cookies to.

指标参考下面几个内容整理。

basic-perfomance
tsar https://github.com/alibaba/tsar/blob/master/info.md#io
netflixs http://techblog.netflix.com/2015/04/introducing-vector-netflixs-on-host.html
openfalcon http://book.open-falcon.com/zh/faq/linux-metrics.html

含义参考了: 对应的 manpage, kernel doc。

	# ########################################################## #
	# Makefile for Golang Project
	# Includes cross-compiling, installation, cleanup
	# ########################################################## #

	# Check for required command tools to build or stop immediately
	EXECUTABLES = git go find pwd
	K := $(foreach exec,$(EXECUTABLES),\
	$(if $(shell which $(exec)),some string,$(error "No $(exec) in PATH)))

	#include <uapi/linux/ptrace.h>
	#include <uapi/linux/if_packet.h>
	#include <net/sock.h>
	#include <bcc/proto.h>

	#define IP_TCP 6
	#define ETH_HLEN 14

	struct Key {
	u32 src_ip; // source ip

	static void get_inode(u64 fd, struct file p_file, struct inode p_inode)
	{
	struct file *file = NULL;
	struct inode *f_inode = NULL;
	#if (LINUX_VERSION_CODE > KERNEL_VERSION(3,7,0))
	file = fget_raw(fd); // do not forget to fput(file)
	#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)) && (LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,255))
	{
	struct files_struct *files = current->files;
	if (files) // This is always the case, but I am not taking chances

	#include<linux/module.h>
	#include<linux/kernel.h>
	#include<linux/string.h>
	#include<linux/vmalloc.h>
	#include<linux/mm.h>
	#include<linux/init.h>
	#include<linux/proc_fs.h>
	#include<linux/sched.h>
	#include<linux/uaccess.h>
	#include<linux/fs.h>

	xstat() {
	for target in "${@}"; do
	inode=$(ls -di "${target}" \| cut -d ' ' -f 1)
	fs=$(df "${target}" \| tail -1 \| awk '{print $1}')
	crtime=$(sudo debugfs -R 'stat <'"${inode}"'>' "${fs}" 2>/dev/null \|
	grep -oP 'crtime.--\s\K.*')
	printf "%s\t%s\n" "${crtime}" "${target}"
	done
	}

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/socket.h>
	#include <netinet/in.h>

	#define SERVER_ADDR "173.194.72.94"
	#define SERVER_PORT 80

	int main()

chenk008

One-liner

Overly aggressive CFS

Reproduction program

Common Options

系统监控