????1??????????????
????????????????????????????????????ó???????????????????????????????????????????????紫?????????????????????web?????????
????80%????????????仨???????????????????????????????????????????????????Flash????????????????????????????HTTP??????????????????????????????
?????????“2-5-8???”??????????????棺
??????????????2????????????????о???????????
???????????2-5???????????????о?????????????????
???????????5-8????????????????о?????????????????????????????
????????????????8????????????????????о??????????????????????????????????????Web??????????????????
????????????????????????????????????????????????????????????????????google????????????????С?
???????????Web Performance Optimization (WPO) – As Business Critical as SEO
????2????????????????
????2.1 ?????????????????????????
????a. Time to First Impression
???????????????????????url?????????????????濪??з?????????????????п??????????????????????о??????????????????????title??
????b.Time to onLoad Event
???????????濪???????????????????????OnLoad??????????Ρ???е?????????????????????????????????????????OnLoad????
????c.Time to Fully Loaded
?????????????????????????????????????????OnLoad????????????????????????????????к???timeout??????????????????ж??????
????2.2 ?????????
?????????????html????????????????XHR???????dom??????????????????css?????????js?????????????????????????????????????????????????????????????????????????????????
????a. Total Number of Requests
????????html???????css??js?????????????????????????????????????????????????
????b. Total Number of HTTP 300s/400s/500s
??????????????300?????????400????????????500???????????????http??????????????Щ????????????load??????????Щ?????????????????????????ú????????
????c. Total Size of Web Site
??????????????????С????????js?????????????????????????????
????d. Total Size of Images/CSS/JS
????image??css??js?????????С????????????
????e. Total Number of XHR(XMLHttpRequest) Requests
???????js???????????????????????????Щjs???????????????????????????XHR?????????????????XHR????????
????2.3 ???????????
???????????????????????????????????к???????????????????????Ρ??????????Щ????????????????硢????????????Щ??ε????
????a. DNS Time
????dns ??????????????????????????????????????????dns??????????????????????л?????????μ?dns?????
????b. Connect Time
???????????????????佨??tcp/ip????????????ssl???????????????????????????????ssl????????????????????????connect time???????
????c. Server Time
?????????????????????????????
????d. Transfer Time
???????????????????????????????????????￡??????С????????????cdn??????Transfer Time??
????e. Wait Time
??????????????????з?????????????????????????????????????????????????????????????????????????????????????????????????????????併??????????????С?????????????????????
????f. Number of Domains / Single Resource Domains
????????????????????????????????????????????DNS????????????
??????????????????????????????????????????????????????????????dns?????????????????????????
?????ο????????????????????Key Performance Indicators