????10??11??????web???????

??????????? var arr = ['abc'??'ddadbc'??'adbdcd'??'abcqew'.......] ??????? ????Ч??????????????????????????

????????5G??棬????200T???????????????????????????????????ж???200T?????????????????????????????

????????????????????? ?????????

???????????????????200g?????????????????????????ò????????Bloom Filter??http://blog.csdn.net/v_july_v/article/details/6685894??????????200T????????????

????OK????????@cy ???????(???????????????????????????????????????в??????????裬????????λ???????????????????ū???????????????????????????)??

????“??. ??????????? 5GB / 200TB?? ?? 1 ?? 4w?? ????trie??????????? ????hash.

??????. ??????????????????????(????????5GB)

????1. ??MB?? ??????MB?????????????? ???????????Ч???к????? ?????????case????????????????.

??????. ?????????? ????????????? ??? ?????

????1. value ??? 8 ???? key??4???

????1. 200TB????? 200 * 2^40 λ?? ???????????48??bit?? ?洢??????16bit??????????value ???8?????

????1. ??????????????????? ??????? ?????? ??λ????????KB?? ????MB?? 16bit????????

????1. key??4???????Щ????? ?????????ò???????λ

????1. ????????????????г???? ????????????? ??????????????п??????? ??п????????.

????2. ??ν??? ??????? ??hash?????????????????????? ???????????????.

??????. ????????? 5GB ??????? 5GB / 8 ?? 4??????.

??????. ???????200TB???????????hash?? ????hash????? ???????? ????????.

????1. hash???????md5??????е??????? ??? mod 4???????

??????. ??????????????? ?????????? key?hash??? value?????????? ??hash????????????????е????? ?? ??????.

??????????? ????hash??? ???????????????????????? ???????????????????? ??kmp??????.

????200TB??????? ?????? 4?? ??????鵱?У? ??????????? 800KB ?????? ?????hash?????? ???????MB???????

???????????????OK.

????????????С?????:

????1. ???????????? ????????????? ??????????????

????1. ?????hash????? ????????????????·?鼫??????

????1. ???????????????? ??????? ???? ????????????С???? ??????????λ??? ???????????????

????1. ???...???Щ????????ò?????????...

???????????????????????????????. ??ζ?5GB??????????? ???hash?????? ????OK??? ??????д??????? ???????????д??. ??????????????????5GB?? ?????????? ?????鰱?? ????? OK????. ????? ??????????????????IO???????? ???? ???????? ???????????????????....”??