[ https://issues.apache.org/jira/browse/HADOOP-908?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Runping Qi updated HADOOP-908: ------------------------------ Attachment: abacus.patch > Hadoop Abacus, a package for performing simple counting/aggregation > ------------------------------------------------------------------- > > Key: HADOOP-908 > URL: https://issues.apache.org/jira/browse/HADOOP-908 > Project: Hadoop > Issue Type: New Feature > Components: contrib/streaming > Reporter: Runping Qi > Assigned To: Runping Qi > Attachments: abacus.patch > > > Hadoop Abacus package is a specialization of map/reduce framework, > specilizing for performing various counting and aggregations. > It offers similar functionalities to Google's SawZall. > Generally speaking, in order to implement an application using Map/Reduce > model, > the developer needs to implement Map and Reduce functions (and possibly > Combine function). > However, for a lot of applications related to counting and statistics > computing, > these functions have very similar characteristics. > Abacus abstracts out the general patterns and provides a package implementing > those patterns. > In particular, the package provides a generic mapper class, a reducer class > and a combiner class, > and a set of built-in value aggregators. It also provides a generic utility > class, ValueAggregatorJob > for creating Abacus jobs. > To create an Abacus job, the user just needs to implement one plugin class > that > is responsible for specifying what aggregators to use and what values are for > which aggregators. > The mapper will call this class in the runtime to generate aggregation ids > and values. > The generic combiner and reducer will aggregate the values associated with > the same > aggregation ids accordingly. Thus, it is much easier to create and run an > Abacus job than > a normal map/reduce job. Since a built-in generic combiner is always used, > the execution is very efficient. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira