??????????????????з??????????????????????????????????
??????????????????(QPS??TPS)????????(RT)??????????????????
????????????CPU????楨Disk I/O??Network I/O??????????????
????????????????Щ?????????????????????????Щ?????Linux???????????????
?????. CPU
????????CPU??????????????????????????????????????????ж??к????????л???????????????????????????????м???????

????Process state -via wikipedia
????Running?????????е????
????Waiting?????????????????е????
????Blocked?????????Щ??????????????????????????I/O????Disk I/O??Network I/O???
?????????Running??Waiting???????Linux???????е????????(task_running)????Blocked????????Linux???????е?????ж??????(task_uninterruptible)
??????Linux???????vmstat???????Щ?????
[hbase@ecs-097 ~]$ vmstat 1
procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu-----
r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
6  0      0 4591436 176804 1185380    0    0     0     0 7915 10357 83  5 12  0  0
????CPU?????(CPU Utilization Percentages)???н??????Running???????/???????vmstat??????us??sys??id???????????????
????· us????????CPU?????
????· sy????(?????ж?)???CPU?????
????· id??CPU???е????
???????????????У?CPU??????????us + sy?????????????????????70%~80%?????????????????????????У????sy??????????25%????ù??in(???ж?)??cs(???????л?)???????????????????????????????????????
???????ж??н?????(Processes on run queue)??Running?? + Waiting??????????????????????к???CPU????????????????????CPU??????嵥?????ж?CPU?????????????????????vmstat???r??????????
????· r?? ?????н???????????????????(Running)?????????????(Waiting)???
???????r?????????CPU????????????CPU????????ɡ??????????У????????????????????CPU??????2????
???????????л?(Context Switches)?????????context?CPU????????????????????????????(????)???????л???kernel???????????????y??????????洢????棬????????л??????????е??????????????????????????????????д?????????????????????????л???????sy???????vmstat???cs??????????
????· cs????????????л???????
????????????????????????????????????????????ο???
???????????Load Average????UNIX???У?Load??????????????????Load?????????????????UNIX??????ж??е??(vmstat?????r)????Linux??????ж??е?? + ????task_uninterruptible?????????(vmstat?????b)??????????CPU?????????Load??????????Load Average???????????????????????????top??uptime????1?????5?????15???????????????
????[hbase@ecs-097 ~]$ top
????top - 19:23:28 up 18:05??  3 users??  load average: 0.80?? 0.60?? 0.53
????????????е?0.80????1???????Load average??????????
????????????????????????????????????Load average??????????????????????(??15??????????????CPU???????????)?????vmstat??r???b????????CPU???????????I/O????????