????4.????I/O????

????????dd if=/dev/zero of=test bs=64k count=16k oflag=dsync

???????????????????I/O??????????д???д???????????????ο???

????????????????dd if=/dev/zero of=test bs=64k count=4k oflag=dsync

??????С????????????????????DD??????????????????????????к????????????????DD?????1M/s??VPS??????????

????SSD?????????????hdparm -t /dev/xvda

?????????????????????????????2???????100mb.test??test????????????????????

????rm 100mb.test                       rm test

????5.UBI?????????????

????????wget http://www.CTOHome.com/linux-vps-pack/unixbench.sh;sh./unixbench.sh;

??????????????е??????????????VPS?????????????С??????????????????????????????????????????????????????????????VPS?????????????400???????????????????1000???????????????

????6.????????????

????????iostat  ????????????????

????????Vmstat  ?????????楨???I/O???CPU??????????