| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * |
| * Licensed 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. |
| */ |
| |
| package android.net.util; |
| |
| /** |
| * Collection of utilities for data stall. |
| */ |
| public class DataStallUtils { |
| /** |
| * Detect data stall via using dns timeout counts. |
| */ |
| public static final int DATA_STALL_EVALUATION_TYPE_DNS = 1; |
| // Default configuration values for data stall detection. |
| public static final int DEFAULT_CONSECUTIVE_DNS_TIMEOUT_THRESHOLD = 5; |
| public static final int DEFAULT_DATA_STALL_MIN_EVALUATE_TIME_MS = 60 * 1000; |
| public static final int DEFAULT_DATA_STALL_VALID_DNS_TIME_THRESHOLD_MS = 30 * 60 * 1000; |
| /** |
| * The threshold value for the number of consecutive dns timeout events received to be a |
| * signal of data stall. The number of consecutive timeouts needs to be {@code >=} this |
| * threshold to be considered a data stall. Set the value to {@code <= 0} to disable. Note |
| * that the value should be {@code > 0} if the DNS data stall detection is enabled. |
| * |
| */ |
| public static final String CONFIG_DATA_STALL_CONSECUTIVE_DNS_TIMEOUT_THRESHOLD = |
| "data_stall_consecutive_dns_timeout_threshold"; |
| |
| /** |
| * The minimal time interval in milliseconds for data stall reevaluation. |
| * |
| */ |
| public static final String CONFIG_DATA_STALL_MIN_EVALUATE_INTERVAL = |
| "data_stall_min_evaluate_interval"; |
| |
| /** |
| * DNS timeouts older than this timeout (in milliseconds) are not considered for detecting |
| * a data stall. |
| * |
| */ |
| public static final String CONFIG_DATA_STALL_VALID_DNS_TIME_THRESHOLD = |
| "data_stall_valid_dns_time_threshold"; |
| |
| /** |
| * Which data stall detection signal to use. This is a bitmask constructed by bitwise-or-ing |
| * (i.e. {@code |}) the DATA_STALL_EVALUATION_TYPE_* values. |
| * |
| * Type: int |
| * Valid values: |
| * {@link #DATA_STALL_EVALUATION_TYPE_DNS} : Use dns as a signal. |
| */ |
| public static final String CONFIG_DATA_STALL_EVALUATION_TYPE = "data_stall_evaluation_type"; |
| public static final int DEFAULT_DATA_STALL_EVALUATION_TYPES = DATA_STALL_EVALUATION_TYPE_DNS; |
| // The default number of DNS events kept of the log kept for dns signal evaluation. Each event |
| // is represented by a {@link com.android.server.connectivity.NetworkMonitor#DnsResult} objects. |
| // It's also the size of array of {@link com.android.server.connectivity.nano.DnsEvent} kept in |
| // metrics. Note that increasing the size may cause statsd log buffer bust. Need to check the |
| // design in statsd when you try to increase the size. |
| public static final int DEFAULT_DNS_LOG_SIZE = 20; |
| } |