Yes, sorry. You are correct. So basically then it would consume only at least 9x the memory.
/Manuel On 08.03.2012, at 15:01, Sebastian Schelter wrote: > A long has 8 bytes :) > > On 08.03.2012 14:53, Manuel Blechschmidt wrote: >> Hallo Claudia, >> the reason why longs are use is pure efficiency. When you have a lot of >> things and a lot of users and you are using Strings as identifiers you will >> need a lot of memory just for saving them. Further processes like equals or >> hash codes will take longer. >> >> So a long has 4 bytes (64 bits) a UUID string (e.g. >> 936DA01F-9ABD-4D9D-80C7-02AF85C822A8) encoded as utf-16 has 72 bytes that >> means that UUID would consume more then18x the memory that longs are taking. >> >> /Manuel >> >> >> On 08.03.2012, at 14:27, Claudia Grieco wrote: >> >>> Do you think it's worth the work to change the internal code of Mahout in >>> order to use string identifiers? >>> Thanks >>> Claudia >>> >>> -----Messaggio originale----- >>> Da: Manuel Blechschmidt [mailto:[email protected]] >>> Inviato: lunedì 5 marzo 2012 11.28 >>> A: [email protected] >>> Oggetto: Re: Using recommenders with String identifiers >>> >>> Hi Claudia, >>> you have to use an IDMigrator. >>> >>> The following projects shows you an example: >>> https://github.com/ManuelB/facebook-recommender-demo >>> >>> https://github.com/ManuelB/facebook-recommender-demo/blob/master/src/main/ja >>> va/de/apaxo/bedcon/FacebookRecommender.java >>> >>> Good luck >>> Manuel >>> >>> On 05.03.2012, at 09:53, Claudia Grieco wrote: >>> >>>> Hi guys, >>>> >>>> I'd like to use mahout to implement a recommender but I'm encountering a >>>> problem: >>>> >>>> Ids of items and users are represented in Mahout as long integers, while >>> my >>>> data comes from an external database that uses strings to identify items >>> and >>>> users. >>>> >>>> Any suggestion as to how I can fix this problem? >>>> >>>> Thanks a lot >>>> >>>> Claudia >>>> >>> >>> -- >>> Manuel Blechschmidt >>> Dortustr. 57 >>> 14467 Potsdam >>> Mobil: 0173/6322621 >>> Twitter: http://twitter.com/Manuel_B >>> >>> >> > -- Manuel Blechschmidt Dortustr. 57 14467 Potsdam Mobil: 0173/6322621 Twitter: http://twitter.com/Manuel_B
