// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

namespace cpp impala
namespace java org.apache.impala.thrift

// NOTE: The definitions in this file are part of the binary format of the Impala query
// profiles. They should preserve backwards compatibility and as such some rules apply
// when making changes. Please see RuntimeProfile.thrift for more details.


// Metric and counter data types.
//
// WARNING (IMPALA-8236): Adding new values to TUnit and using them in TCounter will break
// old decoders of thrift profiles. The workaround is to only use the following units in
// anything that is serialised into a TCounter:
// UNIT, UNIT_PER_SECOND, CPU_TICKS, BYTES, BYTES_PER_SECOND, TIME_NS, DOUBLE_VALUE
enum TUnit {
  // A dimensionless numerical quantity
  UNIT = 0
  // Rate of a dimensionless numerical quantity
  UNIT_PER_SECOND = 1
  CPU_TICKS = 2
  BYTES = 3
  BYTES_PER_SECOND = 4
  TIME_NS = 5
  DOUBLE_VALUE = 6
  // No units at all, may not be a numerical quantity
  NONE = 7
  TIME_MS = 8
  TIME_S = 9
  TIME_US = 10
  // 100th of a percent, used to express ratios etc., range from 0 to 10000, pretty
  // printed as integer percentages from 0 to 100.
  BASIS_POINTS = 11
}

// The kind of value that a metric represents.
enum TMetricKind {
  // May go up or down over time
  GAUGE = 0
  // A strictly increasing value
  COUNTER = 1
  // Fixed; will never change
  PROPERTY = 2
  STATS = 3
  SET = 4
  HISTOGRAM = 5
}