[
https://issues.apache.org/jira/browse/HBASE-3529?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13001289#comment-13001289
]
stack commented on HBASE-3529:
------------------------------
OK.
Why niopositional read? How is that different than the pread that is already
in the dfsclient api? You don't like going via the Block API? Above you say
in parens '...(using FileChannel.read(ByteBuffer dst, long position)...' What
if the data is not local, usually it is (> 99% of the time), but is not always;
e.g. in time of failure or perhaps after a rebalance. You going to get the
FileChannel off the socket (thats the nio bit)?
You do get the bit that hdfs-347 is a naughty hack as is. A version that
respects 'security', where the 'cleared' fd is passed via unix domain sockets,
for the dfsclient to use going direct is probably what'll go in sometime soon
hopefully.
You are messing down deep below hbase in dfs. I'm a little worried that you'll
do a bunch of custom work that may work for your lucene directory
implementation but that it will be so particular, it won't be accepted back
into hdfs.
> Add search to HBase
> -------------------
>
> Key: HBASE-3529
> URL: https://issues.apache.org/jira/browse/HBASE-3529
> Project: HBase
> Issue Type: Improvement
> Affects Versions: 0.90.0
> Reporter: Jason Rutherglen
>
> Using the Apache Lucene library we can add freetext search to HBase. The
> advantages of this are:
> * HBase is highly scalable and distributed
> * HBase is realtime
> * Lucene is a fast inverted index and will soon be realtime (see LUCENE-2312)
> * Lucene offers many types of queries not currently available in HBase (eg,
> AND, OR, NOT, phrase, etc)
> * It's easier to build scalable realtime systems on top of already
> architecturally sound, scalable realtime data system, eg, HBase.
> * Scaling realtime search will be as simple as scaling HBase.
> Phase 1 - Indexing:
> * Integrate Lucene into HBase such that an index mirrors a given region.
> This means cascading add, update, and deletes between a Lucene index and an
> HBase region (and vice versa).
> * Define meta-data to mark a region as indexed, and use a Solr schema to
> allow the user to define the fields and analyzers.
> * Integrate with the HLog to ensure that index recovery can occur properly
> (eg, on region server failure)
> * Mirror region splits with indexes (use Lucene's IndexSplitter?)
> * When a region is written to HDFS, also write the corresponding Lucene index
> to HDFS.
> * A row key will be the ID of a given Lucene document. The Lucene docstore
> will explicitly not be used because the document/row data is stored in HBase.
> We will need to solve what the best data structure for efficiently mapping a
> docid -> row key is. It could be a docstore, field cache, column stride
> fields, or some other mechanism.
> * Write unit tests for the above
> Phase 2 - Queries:
> * Enable distributed Lucene queries
> * Regions that have Lucene indexes are inherently available and may be
> searched on, meaning there's no need for a separate search related system in
> Zookeeper.
> * Integrate search with HBase's RPC mechanism
--
This message is automatically generated by JIRA.
-
For more information on JIRA, see: http://www.atlassian.com/software/jira
