一.理解linux調優指標
1.cpu指標
cpu利用率
應用程序執行的時間
系統執行的時間
cpu等待I/O處理所需要的時間
空間時間
nice處理所需要的時間
cpu負載
能夠處理的任務數
i/o操作被阻止的任務數
中斷數
2.內存指標
空閒內存大小（Free memory）
swap分區大小
buffer和cache
slabs
Active versus inactive memory
3.網卡
包的收發率
收發包的大小
每秒衝突數
丟包情況
網卡buffer溢出情況
包的錯誤情況
4.塊設備
iowait
平均隊列的長列
平均wait
每秒讀寫的block數
每秒讀寫的字節數
二.系統調優工具
top Process activity
vmstat System activity, Hardware and system information
uptime, w Average system load
ps, pstree Displays the processes
free Memory usage
iostat Average CPU load, disk activity
sar Collect and report system activity
mpstat Multiprocessor usage
numastat NUMA-related statistics
pmap Process memory usage
netstat Network statistics
iptraf Real-time network statistics
tcpdump, ethereal Detailed network traffic analysis
nmon Collect and report system activity
strace System calls
Proc file system Various kernel statistics
KDE system guard Real-time systems reporting and graphing
Gnome System Monitor Real-time systems reporting and graphing
lmbench Microbenchmark for operating system functions
iozone File system benchmark
netperf Network performance benchmark