li4wang commented on a change in pull request #1644: URL: https://github.com/apache/zookeeper/pull/1644#discussion_r605845846
########## File path: zookeeper-server/src/main/java/org/apache/zookeeper/server/util/QuotaMetricsUtils.java ########## @@ -0,0 +1,158 @@ +/* + * 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. + */ + +package org.apache.zookeeper.server.util; + +import java.util.Map; +import java.util.Set; +import java.util.concurrent.ConcurrentHashMap; +import org.apache.zookeeper.Quotas; +import org.apache.zookeeper.StatsTrack; +import org.apache.zookeeper.common.PathUtils; +import org.apache.zookeeper.server.DataNode; +import org.apache.zookeeper.server.DataTree; + +public final class QuotaMetricsUtils { + public static final String QUOTA_COUNT_LIMIT_PER_NAMESPACE = "quota_count_limit_per_namespace"; + public static final String QUOTA_BYTES_LIMIT_PER_NAMESPACE = "quota_bytes_limit_per_namespace"; + public static final String QUOTA_COUNT_USAGE_PER_NAMESPACE = "quota_count_usage_per_namespace"; + public static final String QUOTA_BYTES_USAGE_PER_NAMESPACE = "quota_bytes_usage_per_namespace"; + public static final String QUOTA_EXCEEDED_ERROR_PER_NAMESPACE = "quota_exceeded_error_per_namespace"; + + enum QUOTA_LIMIT_USAGE_METRIC_TYPE {QUOTA_COUNT_LIMIT, QUOTA_BYTES_LIMIT, QUOTA_COUNT_USAGE, QUOTA_BYTES_USAGE} + static final String LIMIT_END_STRING = "/" + Quotas.limitNode; + static final String STATS_END_STRING = "/" + Quotas.statNode; + + private QuotaMetricsUtils() { + } + + /** + * Traverse the quota subtree and return per namespace quota count limit + * + * @param dataTree dataTree that contains the quota limit and usage data + * @return a map with top namespace as the key and quota count limit as the value + * + */ + public static Map<String, Number> getQuotaCountLimit(final DataTree dataTree) { + return getQuotaLimitOrUsage(dataTree, QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_COUNT_LIMIT); + } + + /** + * Traverse the quota subtree and return per namespace quota bytes limit + *` + * @param dataTree dataTree that contains the quota limit and usage data + * @return a map with top namespace as the key and quota bytes limit as the value + * + */ + public static Map<String, Number> getQuotaBytesLimit(final DataTree dataTree) { + return getQuotaLimitOrUsage(dataTree, QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_BYTES_LIMIT); + } + + /** + * Traverse the quota subtree and return per namespace quota count usage + * + * @param dataTree dataTree that contains the quota limit and usage data + * @return a map with top namespace as the key and quota count usage as the value + * + */ + public static Map<String, Number> getQuotaCountUsage(final DataTree dataTree) { + return getQuotaLimitOrUsage(dataTree, QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_COUNT_USAGE); + } + + /** + * Traverse the quota subtree and return per namespace quota bytes usage + * + * @param dataTree dataTree that contains the quota limit and usage data + * @return a map with top namespace as the key and quota bytes usage as the value + * + */ + public static Map<String, Number> getQuotaBytesUsage(final DataTree dataTree) { + return getQuotaLimitOrUsage(dataTree, QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_BYTES_USAGE); + } + + // traverse the quota subtree and read the quota limit or usage data + private static Map<String, Number> getQuotaLimitOrUsage(final DataTree dataTree, + final QUOTA_LIMIT_USAGE_METRIC_TYPE type) { + final Map<String, Number> metricsMap = new ConcurrentHashMap<>(); + if (dataTree != null) { + getQuotaLimitOrUsage(Quotas.quotaZookeeper, metricsMap, type, dataTree); + } + return metricsMap; + } + + static void getQuotaLimitOrUsage(final String path, + final Map<String, Number> metricsMap, + final QUOTA_LIMIT_USAGE_METRIC_TYPE type, + final DataTree dataTree) { + final DataNode node = dataTree.getNode(path); + if (node == null) { + return; + } + final Set<String> children = node.getChildren(); + if (children.isEmpty()) { + if (shouldCollect(path, type)) { + collectQuotaLimitOrUsage(path, node, metricsMap, type); + } + return; + } + for (final String child : children) { + getQuotaLimitOrUsage(path + "/" + child, metricsMap, type, dataTree); + } + } + + static boolean shouldCollect(final String path, final QUOTA_LIMIT_USAGE_METRIC_TYPE type) { + return path.endsWith(LIMIT_END_STRING) + && (QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_COUNT_LIMIT == type || QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_BYTES_LIMIT == type) + || path.endsWith(STATS_END_STRING) + && (QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_COUNT_USAGE == type || QUOTA_LIMIT_USAGE_METRIC_TYPE.QUOTA_BYTES_USAGE == type); + } + + static void collectQuotaLimitOrUsage(final String path, + final DataNode node, + final Map<String, Number> metricsMap, + final QUOTA_LIMIT_USAGE_METRIC_TYPE type) { + final String namespace = PathUtils.getTopNamespace(Quotas.trimQuotaPath(path)); + if (namespace == null) { + return; + } + if (node.getData() == null) { + return; + } + final StatsTrack statsTrack = new StatsTrack(node.getData()); + switch (type) { + case QUOTA_COUNT_LIMIT: + metricsMap.put(namespace, getQuotaLimit(statsTrack.getCountHardLimit(), statsTrack.getCount())); + break; + case QUOTA_BYTES_LIMIT: + metricsMap.put(namespace, getQuotaLimit(statsTrack.getByteHardLimit(), statsTrack.getBytes())); + break; + case QUOTA_COUNT_USAGE: + metricsMap.put(namespace, statsTrack.getCount()); + break; + case QUOTA_BYTES_USAGE: + metricsMap.put(namespace, statsTrack.getBytes()); + break; + default: + } + } + + // hard limit takes precedence if specified + static long getQuotaLimit(final long hardLimit, final long limit) { + return hardLimit > -1 ? hardLimit : limit; + } Review comment: Yes, if we change the semantics of soft and hard quotas in the future, we will update the the published metrics along with the changes. Changing the semantics is a fundamental thing, so it makes sense to make all the changes that are impacted at that time. There are two concerns for publishing both soft and hard limit at this point. 1. It doesn't match with the current semantics of soft and hard quotas and make it harder for user t o use the metrics. 2. Given the constraint we have with the current interface of metrics framework, it means the we need to iterate two more times on the /zookeeper/quota tree. IMO, we pay something up-to-front that doesn't give us too much benefits. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
