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stack commented on HBASE-2001: ------------------------------ Are you using HTableInterface for your "table" implementations? +1 that coprocessors be used to implement filters. Would we keep the filter interface as is? With coprocessors, filters would be able to have state that crossed rows and even regions? (Currently state is in-row only). Critical I'd say is that coprocessors are testable without having to spin up servers. They should be testable standalone if possible. > Coprocessors: Colocate arbitrary code with regions > -------------------------------------------------- > > Key: HBASE-2001 > URL: https://issues.apache.org/jira/browse/HBASE-2001 > Project: Hadoop HBase > Issue Type: Sub-task > Reporter: Andrew Purtell > Assignee: Andrew Purtell > Attachments: asm-3.2-bin.zip, asm-transformations.pdf, > org.apache.hadoop.hbase.HCoprocessor.java, > org.apache.hadoop.hbase.HCoprocessor.pdf > > > "Support arbitrary code that runs run next to each region in table. As > regions split and move, coprocessor code should automatically move also." > Use classloader which looks on HDFS. > Associate a list of classes to load with each table. Put this in HRI so it > inherits from table but can be changed on a per region basis (so then those > region specific changes can inherited by daughters). > Not completely arbitrary code, should require implementation of an interface > with callbacks for: > * Open > * Close > * Split > * Compact > * (Multi)get and scanner next() > * (Multi)put > * (Multi)delete > Add method to HRegionInterface for invoking coprocessor methods and > retrieving results. > Add methods in o.a.h.h.regionserver or subpackage which implement convenience > functions for coprocessor methods and consistent/controlled access to > internals: store access, threading, persistent and ephemeral state, scratch > storage, etc. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.