On Sat, Aug 3, 2013 at 8:52 PM, Ted Yu <yuzhih...@gmail.com> wrote: > Does this mean that user code wouldn't be able to depend > on HConnectionManager for connection sharing ? >
My read of the above is that the HConnection instance is shared across consumers, is the shared connection. Am I reading that correctly? On Sat, Aug 3, 2013 at 7:20 AM, Ted Yu <yuzhih...@gmail.com> wrote: > > > Ah, I find the JIRA - HBASE-9117. > > > > Cheers > > > > > > On Fri, Aug 2, 2013 at 10:54 PM, lars hofhansl <la...@apache.org> wrote: > > > >> Yeah, I filed a separate ticket for the API removal in trunk. > >> > >> > >> > >> ________________________________ > >> From: Ted Yu <yuzhih...@gmail.com> > >> To: dev@hbase.apache.org; lars hofhansl <la...@apache.org> > >> Sent: Friday, August 2, 2013 10:31 PM > >> Subject: Re: Heads up, HTablePool will be deprecated in 0.94, 0.95/0.96, > >> and removed in 0.98 > >> > >> > >> bq. HConnectionManager.getConnection() will be removed. > >> > >> I don't see the above change in 6580-trunk.txt > >> Would the above be done in next patch or in another JIRA ? > >> > >> Cheers > >> > >> On Fri, Aug 2, 2013 at 9:29 PM, lars hofhansl <la...@apache.org> wrote: > >> > >> > See. https://issues.apache.org/jira/browse/HBASE-6580 > >> > > >> > The new proposed API looks like this: > >> > > >> > Here's the proposed new API: > >> > * HConnectionManager: > >> > public static HConnection createConnection(Configuration conf) > >> > public static HConnection createConnection(Configuration conf, > >> > ExecutorService pool) > >> > > >> > * HConnection: > >> > public HTableInterface getTable(byte[] tableName) throws > IOException > >> > public HTableInterface getTable(byte[] tableName, ExecutorService > >> > pool) throws IOException > >> > public HTableInterface getTable(String tableName) throws > IOException > >> > > >> > By default HConnectionImplementation will create an ExecutorService > when > >> > needed. The ExecutorService can optionally passed be passed in. > >> > HTableInterfaces are retrieved from the HConnection. By default the > >> > HConnection's ExecutorService is used, but optionally that can be > >> > overridden for each HTable. > >> > > >> > In 0.98/trunk: > >> > > >> > 1. HTablePool will be removed. It is not longer needed. > >> > 2. All constructors in HTable will be removed and changed to be > >> protected. > >> > All code use HTableInterface only. > >> > 3. HConnectionManager.getConnection() will be removed. > >> > 3. All HConnection caching (deleteConnection, etc,etc) will be > removed, > >> as > >> > it is no longer needed. > >> > > >> > > >> > The new flow of setting up a client would look like this: > >> > > >> > ----- Snip ----- > >> > // connection to the cluster > >> > HConnection conn = HConnectionManager.createConnection(conf); > >> > ... > >> > // When the cluster connection is established get an HTableInterface > for > >> > each operation or thread. > >> > // HConnection.getTable(...) is lightweight. The table is really just > a > >> > convenient place to call table method and for a temporary batch cache. > >> > // It is in fact less overhead than HTablePool had when retrieving a > >> > cached HTable. > >> > // The HTableInterface returned is not thread safe as before. > >> > // It's fine to get 1000's of these. > >> > // Don't cache the longer than the lifetime of the HConnection > >> > HTableInterface table = conn.getTable("MyTable"); > >> > ... > >> > // just flushes outstanding commit, no futher cleanup needed, can be > >> > omitted. > >> > // HConnection holds no references to the returned HTable objects, > they > >> > can be GC'd as soon as they leave scope. > >> > table.close(); > >> > ... > >> > conn.close(); // done with the cluster, release resources > >> > ----- Snip ----- > >> > > >> > The HConnection will maintain and share its own ThreadPool for all > batch > >> > operations executed by the HTables. > >> > This can overridden per HConnection and/or per individual HTable > object. > >> > > >> > I will commit the new API to all branches early next week. > >> > > >> > Questions? Comments? Concerns? Praise? > >> > > >> > -- Lars > >> > > > > >
