Configure maximum number of rows that asynchbase reads. Setting to be…

… provided as export HBASE_MAX_ROWS=nnn in src/tsdb.local

src/core/TsdbQuery.java

@@ -108,6 +108,9 @@ final class TsdbQuery implements Query {
  /** Minimum time interval (in seconds) wanted between each data point. */
  private int sample_interval;
 
+ /** Number of hbase rows to scan in one pass */
+ private int max_row_scan;
+
  /** Constructor. */
  public TsdbQuery(final TSDB tsdb) {
  this.tsdb = tsdb;
@@ -386,6 +389,7 @@ private Scanner getScanner() throws HBaseException {
  createAndSetFilter(scanner);
  }
  scanner.setFamily(TSDB.FAMILY);
+ scanner.setMaxNumRows(getMaxHbaseRows());
  return scanner;
  }
 
@@ -578,6 +582,30 @@ public String toString() {
  return buf.toString();
  }
 
+ /**
+ * Return the number of rows asynchbase should scan in one call
+ */
+ private int getMaxHbaseRows() {
+ if(max_row_scan == 0) {
+ String rows = System.getenv("HBASE_MAX_ROWS");
+ try {
+ if(rows != null) {
+ max_row_scan = Integer.parseInt(rows);
+ } else {
+ max_row_scan = 128;
+ }
+ } catch (NumberFormatException e) {
+ // Do nothing
+ }
+ if(max_row_scan <= 0) {
+ LOG.error(rows + " is not a legit value for HBASE_MAX_ROWS");
+ max_row_scan = 128;
+ }
+ LOG.info("HBASE_MAX_ROWS set to " + max_row_scan);
+ }
+ return max_row_scan;
+ }
+
  /**
  * Comparator that ignores timestamps in row keys.
  */