Index: core/src/main/java/org/apache/hadoop/hbase/mapreduce/TableInputFormat.java =================================================================== --- core/src/main/java/org/apache/hadoop/hbase/mapreduce/TableInputFormat.java (revision 929321) +++ core/src/main/java/org/apache/hadoop/hbase/mapreduce/TableInputFormat.java (working copy) @@ -127,14 +127,13 @@ if (conf.get(SCAN_MAXVERSIONS) != null) { scan.setMaxVersions(Integer.parseInt(conf.get(SCAN_MAXVERSIONS))); } - - if (conf.get(SCAN_CACHEBLOCKS) != null) { - scan.setCacheBlocks(Boolean.parseBoolean(conf.get(SCAN_CACHEBLOCKS))); - } if (conf.get(SCAN_CACHEDROWS) != null) { scan.setCaching(Integer.parseInt(conf.get(SCAN_CACHEDROWS))); } + + // false by default, full table scans generate too much BC churn + scan.setCacheBlocks((conf.getBoolean(SCAN_CACHEBLOCKS, false))); } catch (Exception e) { LOG.error(StringUtils.stringifyException(e)); } Index: core/src/main/java/org/apache/hadoop/hbase/mapred/TableRecordReaderImpl.java =================================================================== --- core/src/main/java/org/apache/hadoop/hbase/mapred/TableRecordReaderImpl.java (revision 929321) +++ core/src/main/java/org/apache/hadoop/hbase/mapred/TableRecordReaderImpl.java (working copy) @@ -62,6 +62,7 @@ Scan scan = new Scan(firstRow, endRow); scan.addColumns(trrInputColumns); scan.setFilter(trrRowFilter); + scan.setCacheBlocks(false); this.scanner = this.htable.getScanner(scan); } else { LOG.debug("TIFB.restart, firstRow: " +