???????????
????1????????????-SBC??Simultaneous Browser Connections??
???????????????????????????????????????????????TCP??????????????????????TCP???????????????????
????2????????-QPS??Query Per Second??/RPS??Request Per Second??
????????????2????д???????QPS??????RPS????λ????????????Query=???????????????????????????????????????????http??????GET/POST/HEAD??????????????????????????????????????
????http??????????Close????????????TCP?????
????http??????????Keep-Alive??????????????????????????????????????http?????????????????TCP????????????
????3???????????
???????????????????????????????????????????????????????????????????????????????????????Щ???????????????????????? ??????????????????????????????????????????????????????????????????????????????????????????????????????????????????κ???? ???????????????????????????????????????????????
?????????????
????1?????????????=WEB???????????*session???????/http??????????
????2????????? = ??????? x (???????? + ????????????????)/????????
????3????????????????C = nL/T
????C????????????????n??login session????????L??login session??????????T????????????
????4????????????????C' = C +3????C
????????
?????????????OA??????????3000?????????????400??????????????????????????????????????????????????????4??С??????????????8??С?????????????????????
????C = 400*4/8   ????????thinktime???    ????thinktime?????????C*20% ??10%~20%??
????F = VU *R/T????????F??????????VU??????????????R???????????????????????????T??????????????
????R = T/TS   TS??????????
????5?????????????????????? Seek time??Rotational latency????????I/O?????????1000/(Seek time+Rotational latency)*0.75??????Χ??????????
????6??QPS:???????(Query Per Second) ?????????????????????????????????
????QPS = req/sec = ??????/??
????QPS????? [?????? http_load ???????]
????QPS = ???????? / ( ???????? * ??????? )
????QPS: ????????????????????????????
????7?????QPS:???????80%??????????20%?????????20%????????????
?????????( ??PV?? * 80% ) / ( ??????? * 20% ) = ???????????????(QPS)
????8??PV:????????Page View?? ?????????????????????????????????????
????????????????PV????
???????1???????PV = QPS * 3600 * 6
???????2???????PV = QPS * 3600 * 8
????9??UV:????????Unique Visitor???????????????????????????????00:00-24:00????????????????????η???????????
???????????????????QPS / ?????????QPS = ????????
??????????ceil( ?????PV / ??????????????PV )