private void flush(HRegionServer regionServer, TableName tableName) throws IOException {
    for (HRegion region : regionServer.getRegions(tableName)) {
      region.flush(true);
    }
  }
This test sets the multi size WAAAAAY low and then checks to make sure that gets will still make
progress.
hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestMultiRespectsLimits.java