From commits-return-212696-archive-asf-public=cust-asf.ponee.io@cassandra.apache.org Sat Aug 4 14:14:05 2018 Return-Path: X-Original-To: archive-asf-public@cust-asf.ponee.io Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by mx-eu-01.ponee.io (Postfix) with SMTP id 2B863180674 for ; Sat, 4 Aug 2018 14:14:05 +0200 (CEST) Received: (qmail 50629 invoked by uid 500); 4 Aug 2018 12:14:04 -0000 Mailing-List: contact commits-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@cassandra.apache.org Delivered-To: mailing list commits@cassandra.apache.org Received: (qmail 50618 invoked by uid 99); 4 Aug 2018 12:14:04 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd1-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 04 Aug 2018 12:14:04 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd1-us-west.apache.org (ASF Mail Server at spamd1-us-west.apache.org) with ESMTP id A6594C1247 for ; Sat, 4 Aug 2018 12:14:03 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd1-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: -109.501 X-Spam-Level: X-Spam-Status: No, score=-109.501 tagged_above=-999 required=6.31 tests=[ENV_AND_HDR_SPF_MATCH=-0.5, KAM_ASCII_DIVIDERS=0.8, RCVD_IN_DNSWL_MED=-2.3, SPF_PASS=-0.001, USER_IN_DEF_SPF_WL=-7.5, USER_IN_WHITELIST=-100] autolearn=disabled Received: from mx1-lw-eu.apache.org ([10.40.0.8]) by localhost (spamd1-us-west.apache.org [10.40.0.7]) (amavisd-new, port 10024) with ESMTP id hR2WHkr0ZUpF for ; Sat, 4 Aug 2018 12:14:02 +0000 (UTC) Received: from mailrelay1-us-west.apache.org (mailrelay1-us-west.apache.org [209.188.14.139]) by mx1-lw-eu.apache.org (ASF Mail Server at mx1-lw-eu.apache.org) with ESMTP id BEA6A5F35A for ; Sat, 4 Aug 2018 12:14:01 +0000 (UTC) Received: from jira-lw-us.apache.org (unknown [207.244.88.139]) by mailrelay1-us-west.apache.org (ASF Mail Server at mailrelay1-us-west.apache.org) with ESMTP id EC4B1E25D5 for ; Sat, 4 Aug 2018 12:14:00 +0000 (UTC) Received: from jira-lw-us.apache.org (localhost [127.0.0.1]) by jira-lw-us.apache.org (ASF Mail Server at jira-lw-us.apache.org) with ESMTP id 381B723F9D for ; Sat, 4 Aug 2018 12:14:00 +0000 (UTC) Date: Sat, 4 Aug 2018 12:14:00 +0000 (UTC) From: "ASF GitHub Bot (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (CASSANDRA-14436) Add sampler for query time and expose with nodetool MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/CASSANDRA-14436?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16569158#comment-16569158 ] ASF GitHub Bot commented on CASSANDRA-14436: -------------------------------------------- Github user clohfink commented on a diff in the pull request: https://github.com/apache/cassandra/pull/244#discussion_r207707285 --- Diff: src/java/org/apache/cassandra/metrics/FrequencySampler.java --- @@ -0,0 +1,105 @@ +/* + * 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.cassandra.metrics; + +import java.util.Collections; +import java.util.List; +import java.util.stream.Collectors; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import com.clearspring.analytics.stream.StreamSummary; + +/** + * Find the most frequent sample. A sample adds to the sum of its key ie + *

add("x", 10); and add("x", 20); will result in "x" = 30

This uses StreamSummary to only store the + * approximate cardinality (capacity) of keys. If the number of distinct keys exceed the capacity, the error of the + * sample may increase depending on distribution of keys among the total set. + * + * @param + */ +public abstract class FrequencySampler extends Sampler +{ + private static final Logger logger = LoggerFactory.getLogger(FrequencySampler.class); + private boolean enabled = false; + + private StreamSummary summary; + + /** + * Start to record samples + * + * @param capacity + * Number of sample items to keep in memory, the lower this is + * the less accurate results are. For best results use value + * close to cardinality, but understand the memory trade offs. + */ + public synchronized void beginSampling(int capacity) + { + if (!enabled) + { + summary = new StreamSummary(capacity); + enabled = true; + } + } + + /** + * Call to stop collecting samples, and gather the results + * @param count Number of most frequent items to return + */ + public synchronized List> finishSampling(int count) + { + List> results = Collections.EMPTY_LIST; + if (enabled) + { + enabled = false; + results = summary.topK(count) + .stream() + .map(c -> new Sample(c.getItem(), c.getCount(), c.getError())) + .collect(Collectors.toList()); + } + return results; + } + + protected synchronized void insert(final T item, final long value) + { + // samplerExecutor is single threaded but still need + // synchronization against jmx calls to finishSampling + if (enabled && value > 0) + { + try + { + summary.offer(item, (int) Math.min(value, Integer.MAX_VALUE)); + } catch (Exception e) + { + logger.trace("Failure to offer sample", e); + } + } + } + + public boolean isEnabled() + { + return enabled; + } + + public void setEnabled(boolean enabled) + { + this.enabled = enabled; --- End diff -- That method was unnecessary so I just deleted it > Add sampler for query time and expose with nodetool > --------------------------------------------------- > > Key: CASSANDRA-14436 > URL: https://issues.apache.org/jira/browse/CASSANDRA-14436 > Project: Cassandra > Issue Type: Improvement > Reporter: Chris Lohfink > Assignee: Chris Lohfink > Priority: Major > > Create a new {{nodetool profileload}} that functions just like toppartitions but with more data, returning the slowest local reads and writes on the host during a given duration and highest frequency touched partitions (same as {{nodetool toppartitions}}). Refactor included to extend use of the sampler for uses outside of top frequency (max instead of total sample values). > Future work to this is to include top cpu and allocations by query and possibly tasks/cpu/allocations by stage during time window. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org For additional commands, e-mail: commits-help@cassandra.apache.org