If long periods between next invocations, up the scanner lease. See: <property> <name>hbase.regionserver.lease.period</name> <value>60000</value> <description>HRegion server lease period in milliseconds. Default is 60 seconds. Clients must report in within this period else they are considered dead.</description> </property>
St.Ack On Tue, May 4, 2010 at 7:04 AM, Michelan Arendse <miche...@addynamo.com> wrote: > Yes I am waiting long periods between invocation of next. I didn't know that > I am fetching too much data at once. > > I am using HBase 0.20.3. This is my code: > > scan.setTimeRange(fromDate.getTime(), toDate.getTime()); > ResultScanner scanner = table.getScanner(scan); > > while( (result = scanner.next()) != null) { > channelRow = getChannelDeliveryRow(Bytes.toString(result.getRow())); > channelRowList.add(channelRow); > } > > This is some of the output from the log file: > 2010-05-04 15:27:44,546 DEBUG org.apache.hadoop.hbase.io.hfile.LruBlockCache: > Block cache LRU eviction started. Attempting to free 62791520 bytes > 2010-05-04 15:27:44,552 DEBUG org.apache.hadoop.hbase.io.hfile.LruBlockCache: > Block cache LRU eviction completed. Freed 62797944 bytes. Priority Sizes: > Single=279.4997MB (293076672), Multi=224.35243MB (235250576),Memory=0.0MB (0) > > > -----Original Message----- > From: saint....@gmail.com [mailto:saint....@gmail.com] On Behalf Of Stack > Sent: 04 May 2010 03:55 PM > To: hbase-user@hadoop.apache.org > Subject: Re: Improving HBase scanner > > Are you waiting too long between invocations of next? (i.e. > the > scanner lease period?) Or, perhaps you are fetching too much in the > one go. If you fetch 1000 at a time -- scanner caching -- and you > don't get the next batch within the scanner lease period, again you > will timeout. > > St.Ack > > On Tue, May 4, 2010 at 1:46 AM, Michelan Arendse <miche...@addynamo.com> > wrote: >> Hi >> >> I would like to know how configure HBase to improve the scanner fetching >> data from the table or another method of using scanner, as my database is >> very large and scanner times out. >> >> Kind Regards, >> >> Michelan Arendse >> Junior Developer | AD:DYNAMO // happy business ;-) >> Office 0861 Dynamo (0861 396266) | Fax +27 (0) 21 465 2587 >> >> Advertise Online Instantly - www.addynamo.com<http://www.addynamo.com> >> <http://www.addynamo.com> >> >> >