Examples with AggregationBuffer org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator.AggregationBuffer used on opensource projects

Example 6 with AggregationBuffer

use of org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator.AggregationBuffer in project hive by apache.

the class GroupByOperator method estimateRowSize.

/**
 * @return the size of each row
 */
private void estimateRowSize() throws HiveException {
    // estimate the size of each entry -
    // a datatype with unknown size (String/Struct etc. - is assumed to be 256
    // bytes for now).
    // 64 bytes is the overhead for a reference
    fixedRowSize = javaHashEntryOverHead;
    ArrayList<ExprNodeDesc> keys = conf.getKeys();
    // track of the variable length keys
    for (int pos = 0; pos < keys.size(); pos++) {
        fixedRowSize += getSize(pos, keys.get(pos).getTypeInfo());
    }
    // Go over all the aggregation classes and and get the size of the fields of
    // fixed length. Keep track of the variable length
    // fields in these aggregation classes.
    estimableAggregationEvaluators = new boolean[aggregationEvaluators.length];
    for (int i = 0; i < aggregationEvaluators.length; i++) {
        fixedRowSize += javaObjectOverHead;
        AggregationBuffer agg = aggregationEvaluators[i].getNewAggregationBuffer();
        if (GenericUDAFEvaluator.isEstimable(agg)) {
            estimableAggregationEvaluators[i] = true;
            continue;
        }
        Field[] fArr = ObjectInspectorUtils.getDeclaredNonStaticFields(agg.getClass());
        for (Field f : fArr) {
            fixedRowSize += getSize(i, f.getType(), f);
        }
    }
}