diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml new file mode 100644 index 0000000000..27c5165db1 --- /dev/null +++ b/.github/workflows/maven.yml @@ -0,0 +1,49 @@ +# +# Copyright 2023 The original authors +# +# 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. +# + +name: Build + +on: + push: + branches: [ main ] + pull_request: + branches: [ main ] + +jobs: + build: + runs-on: ubuntu-latest + + steps: + - name: 'Check out repository' + uses: actions/checkout@v2 + with: + submodules: 'true' + + - name: 'Set up Java' + uses: actions/setup-java@v2 + with: + java-version: 21 + distribution: 'temurin' + + - name: 'Cache Maven packages' + uses: actions/cache@v3 + with: + path: ~/.m2 + key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }} + restore-keys: ${{ runner.os }}-m2 + + - name: 'Build project' + run: mvn -B clean verify diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000000..24b8221fab --- /dev/null +++ b/.gitignore @@ -0,0 +1,44 @@ +#Maven +target/ +pom.xml.tag +pom.xml.releaseBackup +pom.xml.versionsBackup +release.properties + +# Eclipse +.project +.classpath +.settings/ +bin/ + +# IntelliJ +.idea +*.ipr +*.iml +*.iws + +# NetBeans +nb-configuration.xml + +# Visual Studio Code +.vscode +.factorypath + +# OSX +.DS_Store + +# Vim +*.swp +*.swo + +# patch +*.orig +*.rej + +# Local environment +.env + +#JReleaser +out/ + +measurements.txt diff --git a/.mvn/wrapper/maven-wrapper.jar b/.mvn/wrapper/maven-wrapper.jar new file mode 100644 index 0000000000..cb28b0e37c Binary files /dev/null and b/.mvn/wrapper/maven-wrapper.jar differ diff --git a/.mvn/wrapper/maven-wrapper.properties b/.mvn/wrapper/maven-wrapper.properties new file mode 100644 index 0000000000..e347d2d249 --- /dev/null +++ b/.mvn/wrapper/maven-wrapper.properties @@ -0,0 +1,18 @@ +# 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. +distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.8.4/apache-maven-3.8.4-bin.zip +wrapperUrl=https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.2.0/maven-wrapper-3.2.0.jar diff --git a/LICENSE.txt b/LICENSE.txt new file mode 100644 index 0000000000..7a4a3ea242 --- /dev/null +++ b/LICENSE.txt @@ -0,0 +1,202 @@ + + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright [yyyy] [name of copyright owner] + + 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. \ No newline at end of file diff --git a/README.md b/README.md new file mode 100644 index 0000000000..042545b101 --- /dev/null +++ b/README.md @@ -0,0 +1,133 @@ +# 1️⃣🐝🏎️ The One Billion Row Challenge + +The One Billion Row Challenge (1BRC) is a fun exploration of how far modern Java can be pushed for aggregating one billion rows from a text file. + +The text file contains temperature values for a range of weather stations. +Each row is one measurement in the format `;`. +The following shows ten rows as an example: + +``` +hamburg;11.0 +hammerfest;-12.7 +auckland;5.3 +lima;6.6 +concordia;-42.5 +hammerfest;-6.7 +hamburg;9.0 +hammerfest;-11.9 +hamburg;-0.7 +concordia;-48.5 +``` + +The task is to write a Java program which reads the file, calculates the average temperature value per weather station, and emits the result on stdout like this: + +``` +{auckland=5.3, concordia=-45.5, hamburg=6.4, hammerfest=-10.4, lima=6.6} +``` + +## Results + +| # | Result (sec) | Implementation | Submitter | +|---|--------------|----------------|---------------| +| 1.| 200.150| [CalculateAverage.java](https://github.com/gunnarmorling/onebrc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage.java) (baseline)| Gunnar Morling| + +See [below](#entering-the-challenge) for instructions how to enter the challenge with your own implementation. + +## Prerequisites + +[Java 21](https://openjdk.org/projects/jdk/21/) must be installed on your system. + +## Running the Challenge + +This repository contains two programs: + +* `dev.morling.onebrc.CreateMeasurements` (invoked via _create\_measurements.sh_): Creates the file _measurements.txt_ in the root directory of this project with a configurable number of random measurement values +* `dev.morling.onebrc.CalculateAverage` (invoked via _calculate\_average.sh_): Calculates the average values for the file _measurements.txt_ + +Execute the following steps to run the challenge: + +1. Build the project using Apache Maven: + + ``` + ./mvnw clean verify + ``` + +2. Create the measurements file with 1B rows (just once): + + ``` + ./create_measurements.sh 1000000000 + ``` + + This will take a few minutes. + **Attention:** the generated file has a size of approx. 12 GB, so make sure to have enough diskspace. + +3. Calculate the average measurement values: + + ``` + ./calculate_average.sh + ``` + + The provided naive example implementation uses the Java streams API for processing the file and completes the task in ~3 min on an Apple Mac Mini M1. + It serves as the base line for comparing your own implementation. + +4. Optimize the Heck Out Of It: + + Adjust the `CalculateAverage` program to speed it up, in any way you see fit (just sticking to a few rules described below). + Options include parallelizing the computation, using the (incubating) Vector API, memory-mapping different sections of the file concurrently, using AppCDS, GraalVM, CRaC, etc. for speeding up the application start-up, +choosing and tuning the garbage collector, and much more. + +The following rules and limits apply: + +* Any Java distribution provided by [SDKMan](https://sdkman.io/jdks) as well as early access builds available on openjdk.net may be used (including EA builds for OpenJDK projects like Valhalla). +If you want to use a build not available via these channels, reach out to discuss whether it can be considered. +* No external library dependencies may be used +* Implementations must be provided as a single source file + +## Entering the Challenge + +To submit your own implementation to 1BRC, follow these steps: + +* Create a fork of the [onebrc](https://github.com/gunnarmorling/onebrc/) GitHub repository. +* Create a copy of _CalculateAverage.java_, named _CalculateAverage\_.java_, e.g. _CalculateAverage\_doloreswilson.java_. +* Make that implementation fast. Really fast. +* Create a copy of _calculate_average.sh_, named _calculate\_average\_.sh_, e.g. _calculate\_average\_doloreswilson.sh_. +* Adjust that script so that it references your implementation class name. If needed, provide any JVM arguments via the `JAVA_OPTS` variable in that script. +* (Optional) If you'd like to use native binaries (GraalVM), adjust the _pom.xml_ file so that it builds that binary. +* Create a pull request against the upstream repository, clearly stating + * The name of your implementation class. + * The JDK build to use (of not specified, the latest OpenJDK 21 upstream build will be used). +* I will run the program and determine its performance as described in the next section, and enter the result to the scoreboard. + +There is no pre-defined end date or maximum number of results for this challenge at this point, +but I may do a cut-off at some point. +To keep overhead low, please refrain from submitting entries if they wouldn't make it to the top half of the score board. + +## Evaluating Results + +Results are determined by running the program on a [Hetzner Cloud CCX33 instance](https://www.hetzner.com/cloud) (8 dedicated vCPU, 32 GB RAM). +The `time` program is used for measuring execution times, i.e. end-to-end times are measured. +Each contender will be run five times in a row. +The slowest and the fastest runs are discarded. +The mean value of the remaining three runs is the result for that contender and will be added to the results table above. + +If you'd like to spin up your own box for testing on Hetzner Cloud, you may find these [set-up scripts](https://github.com/gunnarmorling/cloud-boxes/) (based on Terraform and Ansible) useful. +Note this will incur cost you are responsible for, I am not going to pay your cloud bill :) + +## Price + +If you enter this challenge, you may learn something new, get to inspire others, and see your name listed in the scoreboard above. + +## FAQ + +_Q: Can I use Kotlin or other JVM languages other than Java?_ +A: No, this challenge is focussed on Java only. Feel free to inofficially share implementations significantly outperforming any listed results, though. + +_Q: Can I use non-JVM languages and/or tools?_ +A: No, this challenge is focussed on Java only. Feel free to inofficially share interesting implementations and results though. For instance it would be interesting to see how DuckDB fares with this task. + +_Q: Why_ 1️⃣🐝🏎️ _?_ +A: It's the abbreviation of the project name: One B R C. + +## License + +This code base is available under the Apache License, version 2. diff --git a/calculate_average.sh b/calculate_average.sh new file mode 100755 index 0000000000..b095e72683 --- /dev/null +++ b/calculate_average.sh @@ -0,0 +1,4 @@ +#!/bin/sh + +JAVA_OPTS="" +java $JAVA_OPTS --class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CalculateAverage diff --git a/create_measurements.sh b/create_measurements.sh new file mode 100755 index 0000000000..4229635577 --- /dev/null +++ b/create_measurements.sh @@ -0,0 +1,3 @@ +#!/bin/sh + +java --class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CreateMeasurements $1 diff --git a/etc/eclipse-formatter-config.xml b/etc/eclipse-formatter-config.xml new file mode 100644 index 0000000000..2a3306ce0d --- /dev/null +++ b/etc/eclipse-formatter-config.xml @@ -0,0 +1,366 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/etc/license.txt b/etc/license.txt new file mode 100644 index 0000000000..69b867170a --- /dev/null +++ b/etc/license.txt @@ -0,0 +1,13 @@ + Copyright 2023 The original authors + + 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. diff --git a/mvnw b/mvnw new file mode 100755 index 0000000000..8d937f4c14 --- /dev/null +++ b/mvnw @@ -0,0 +1,308 @@ +#!/bin/sh +# ---------------------------------------------------------------------------- +# 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. +# ---------------------------------------------------------------------------- + +# ---------------------------------------------------------------------------- +# Apache Maven Wrapper startup batch script, version 3.2.0 +# +# Required ENV vars: +# ------------------ +# JAVA_HOME - location of a JDK home dir +# +# Optional ENV vars +# ----------------- +# MAVEN_OPTS - parameters passed to the Java VM when running Maven +# e.g. to debug Maven itself, use +# set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000 +# MAVEN_SKIP_RC - flag to disable loading of mavenrc files +# ---------------------------------------------------------------------------- + +if [ -z "$MAVEN_SKIP_RC" ] ; then + + if [ -f /usr/local/etc/mavenrc ] ; then + . /usr/local/etc/mavenrc + fi + + if [ -f /etc/mavenrc ] ; then + . /etc/mavenrc + fi + + if [ -f "$HOME/.mavenrc" ] ; then + . "$HOME/.mavenrc" + fi + +fi + +# OS specific support. $var _must_ be set to either true or false. +cygwin=false; +darwin=false; +mingw=false +case "$(uname)" in + CYGWIN*) cygwin=true ;; + MINGW*) mingw=true;; + Darwin*) darwin=true + # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home + # See https://developer.apple.com/library/mac/qa/qa1170/_index.html + if [ -z "$JAVA_HOME" ]; then + if [ -x "/usr/libexec/java_home" ]; then + JAVA_HOME="$(/usr/libexec/java_home)"; export JAVA_HOME + else + JAVA_HOME="/Library/Java/Home"; export JAVA_HOME + fi + fi + ;; +esac + +if [ -z "$JAVA_HOME" ] ; then + if [ -r /etc/gentoo-release ] ; then + JAVA_HOME=$(java-config --jre-home) + fi +fi + +# For Cygwin, ensure paths are in UNIX format before anything is touched +if $cygwin ; then + [ -n "$JAVA_HOME" ] && + JAVA_HOME=$(cygpath --unix "$JAVA_HOME") + [ -n "$CLASSPATH" ] && + CLASSPATH=$(cygpath --path --unix "$CLASSPATH") +fi + +# For Mingw, ensure paths are in UNIX format before anything is touched +if $mingw ; then + [ -n "$JAVA_HOME" ] && [ -d "$JAVA_HOME" ] && + JAVA_HOME="$(cd "$JAVA_HOME" || (echo "cannot cd into $JAVA_HOME."; exit 1); pwd)" +fi + +if [ -z "$JAVA_HOME" ]; then + javaExecutable="$(which javac)" + if [ -n "$javaExecutable" ] && ! [ "$(expr "\"$javaExecutable\"" : '\([^ ]*\)')" = "no" ]; then + # readlink(1) is not available as standard on Solaris 10. + readLink=$(which readlink) + if [ ! "$(expr "$readLink" : '\([^ ]*\)')" = "no" ]; then + if $darwin ; then + javaHome="$(dirname "\"$javaExecutable\"")" + javaExecutable="$(cd "\"$javaHome\"" && pwd -P)/javac" + else + javaExecutable="$(readlink -f "\"$javaExecutable\"")" + fi + javaHome="$(dirname "\"$javaExecutable\"")" + javaHome=$(expr "$javaHome" : '\(.*\)/bin') + JAVA_HOME="$javaHome" + export JAVA_HOME + fi + fi +fi + +if [ -z "$JAVACMD" ] ; then + if [ -n "$JAVA_HOME" ] ; then + if [ -x "$JAVA_HOME/jre/sh/java" ] ; then + # IBM's JDK on AIX uses strange locations for the executables + JAVACMD="$JAVA_HOME/jre/sh/java" + else + JAVACMD="$JAVA_HOME/bin/java" + fi + else + JAVACMD="$(\unset -f command 2>/dev/null; \command -v java)" + fi +fi + +if [ ! -x "$JAVACMD" ] ; then + echo "Error: JAVA_HOME is not defined correctly." >&2 + echo " We cannot execute $JAVACMD" >&2 + exit 1 +fi + +if [ -z "$JAVA_HOME" ] ; then + echo "Warning: JAVA_HOME environment variable is not set." +fi + +# traverses directory structure from process work directory to filesystem root +# first directory with .mvn subdirectory is considered project base directory +find_maven_basedir() { + if [ -z "$1" ] + then + echo "Path not specified to find_maven_basedir" + return 1 + fi + + basedir="$1" + wdir="$1" + while [ "$wdir" != '/' ] ; do + if [ -d "$wdir"/.mvn ] ; then + basedir=$wdir + break + fi + # workaround for JBEAP-8937 (on Solaris 10/Sparc) + if [ -d "${wdir}" ]; then + wdir=$(cd "$wdir/.." || exit 1; pwd) + fi + # end of workaround + done + printf '%s' "$(cd "$basedir" || exit 1; pwd)" +} + +# concatenates all lines of a file +concat_lines() { + if [ -f "$1" ]; then + # Remove \r in case we run on Windows within Git Bash + # and check out the repository with auto CRLF management + # enabled. Otherwise, we may read lines that are delimited with + # \r\n and produce $'-Xarg\r' rather than -Xarg due to word + # splitting rules. + tr -s '\r\n' ' ' < "$1" + fi +} + +log() { + if [ "$MVNW_VERBOSE" = true ]; then + printf '%s\n' "$1" + fi +} + +BASE_DIR=$(find_maven_basedir "$(dirname "$0")") +if [ -z "$BASE_DIR" ]; then + exit 1; +fi + +MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}; export MAVEN_PROJECTBASEDIR +log "$MAVEN_PROJECTBASEDIR" + +########################################################################################## +# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central +# This allows using the maven wrapper in projects that prohibit checking in binary data. +########################################################################################## +wrapperJarPath="$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" +if [ -r "$wrapperJarPath" ]; then + log "Found $wrapperJarPath" +else + log "Couldn't find $wrapperJarPath, downloading it ..." + + if [ -n "$MVNW_REPOURL" ]; then + wrapperUrl="$MVNW_REPOURL/org/apache/maven/wrapper/maven-wrapper/3.2.0/maven-wrapper-3.2.0.jar" + else + wrapperUrl="https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.2.0/maven-wrapper-3.2.0.jar" + fi + while IFS="=" read -r key value; do + # Remove '\r' from value to allow usage on windows as IFS does not consider '\r' as a separator ( considers space, tab, new line ('\n'), and custom '=' ) + safeValue=$(echo "$value" | tr -d '\r') + case "$key" in (wrapperUrl) wrapperUrl="$safeValue"; break ;; + esac + done < "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.properties" + log "Downloading from: $wrapperUrl" + + if $cygwin; then + wrapperJarPath=$(cygpath --path --windows "$wrapperJarPath") + fi + + if command -v wget > /dev/null; then + log "Found wget ... using wget" + [ "$MVNW_VERBOSE" = true ] && QUIET="" || QUIET="--quiet" + if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then + wget $QUIET "$wrapperUrl" -O "$wrapperJarPath" || rm -f "$wrapperJarPath" + else + wget $QUIET --http-user="$MVNW_USERNAME" --http-password="$MVNW_PASSWORD" "$wrapperUrl" -O "$wrapperJarPath" || rm -f "$wrapperJarPath" + fi + elif command -v curl > /dev/null; then + log "Found curl ... using curl" + [ "$MVNW_VERBOSE" = true ] && QUIET="" || QUIET="--silent" + if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then + curl $QUIET -o "$wrapperJarPath" "$wrapperUrl" -f -L || rm -f "$wrapperJarPath" + else + curl $QUIET --user "$MVNW_USERNAME:$MVNW_PASSWORD" -o "$wrapperJarPath" "$wrapperUrl" -f -L || rm -f "$wrapperJarPath" + fi + else + log "Falling back to using Java to download" + javaSource="$MAVEN_PROJECTBASEDIR/.mvn/wrapper/MavenWrapperDownloader.java" + javaClass="$MAVEN_PROJECTBASEDIR/.mvn/wrapper/MavenWrapperDownloader.class" + # For Cygwin, switch paths to Windows format before running javac + if $cygwin; then + javaSource=$(cygpath --path --windows "$javaSource") + javaClass=$(cygpath --path --windows "$javaClass") + fi + if [ -e "$javaSource" ]; then + if [ ! -e "$javaClass" ]; then + log " - Compiling MavenWrapperDownloader.java ..." + ("$JAVA_HOME/bin/javac" "$javaSource") + fi + if [ -e "$javaClass" ]; then + log " - Running MavenWrapperDownloader.java ..." + ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$wrapperUrl" "$wrapperJarPath") || rm -f "$wrapperJarPath" + fi + fi + fi +fi +########################################################################################## +# End of extension +########################################################################################## + +# If specified, validate the SHA-256 sum of the Maven wrapper jar file +wrapperSha256Sum="" +while IFS="=" read -r key value; do + case "$key" in (wrapperSha256Sum) wrapperSha256Sum=$value; break ;; + esac +done < "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.properties" +if [ -n "$wrapperSha256Sum" ]; then + wrapperSha256Result=false + if command -v sha256sum > /dev/null; then + if echo "$wrapperSha256Sum $wrapperJarPath" | sha256sum -c > /dev/null 2>&1; then + wrapperSha256Result=true + fi + elif command -v shasum > /dev/null; then + if echo "$wrapperSha256Sum $wrapperJarPath" | shasum -a 256 -c > /dev/null 2>&1; then + wrapperSha256Result=true + fi + else + echo "Checksum validation was requested but neither 'sha256sum' or 'shasum' are available." + echo "Please install either command, or disable validation by removing 'wrapperSha256Sum' from your maven-wrapper.properties." + exit 1 + fi + if [ $wrapperSha256Result = false ]; then + echo "Error: Failed to validate Maven wrapper SHA-256, your Maven wrapper might be compromised." >&2 + echo "Investigate or delete $wrapperJarPath to attempt a clean download." >&2 + echo "If you updated your Maven version, you need to update the specified wrapperSha256Sum property." >&2 + exit 1 + fi +fi + +MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS" + +# For Cygwin, switch paths to Windows format before running java +if $cygwin; then + [ -n "$JAVA_HOME" ] && + JAVA_HOME=$(cygpath --path --windows "$JAVA_HOME") + [ -n "$CLASSPATH" ] && + CLASSPATH=$(cygpath --path --windows "$CLASSPATH") + [ -n "$MAVEN_PROJECTBASEDIR" ] && + MAVEN_PROJECTBASEDIR=$(cygpath --path --windows "$MAVEN_PROJECTBASEDIR") +fi + +# Provide a "standardized" way to retrieve the CLI args that will +# work with both Windows and non-Windows executions. +MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $*" +export MAVEN_CMD_LINE_ARGS + +WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain + +# shellcheck disable=SC2086 # safe args +exec "$JAVACMD" \ + $MAVEN_OPTS \ + $MAVEN_DEBUG_OPTS \ + -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \ + "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \ + ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@" diff --git a/mvnw.cmd b/mvnw.cmd new file mode 100644 index 0000000000..f80fbad3e7 --- /dev/null +++ b/mvnw.cmd @@ -0,0 +1,205 @@ +@REM ---------------------------------------------------------------------------- +@REM Licensed to the Apache Software Foundation (ASF) under one +@REM or more contributor license agreements. See the NOTICE file +@REM distributed with this work for additional information +@REM regarding copyright ownership. The ASF licenses this file +@REM to you under the Apache License, Version 2.0 (the +@REM "License"); you may not use this file except in compliance +@REM with the License. You may obtain a copy of the License at +@REM +@REM http://www.apache.org/licenses/LICENSE-2.0 +@REM +@REM Unless required by applicable law or agreed to in writing, +@REM software distributed under the License is distributed on an +@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +@REM KIND, either express or implied. See the License for the +@REM specific language governing permissions and limitations +@REM under the License. +@REM ---------------------------------------------------------------------------- + +@REM ---------------------------------------------------------------------------- +@REM Apache Maven Wrapper startup batch script, version 3.2.0 +@REM +@REM Required ENV vars: +@REM JAVA_HOME - location of a JDK home dir +@REM +@REM Optional ENV vars +@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands +@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending +@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven +@REM e.g. to debug Maven itself, use +@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000 +@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files +@REM ---------------------------------------------------------------------------- + +@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on' +@echo off +@REM set title of command window +title %0 +@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on' +@if "%MAVEN_BATCH_ECHO%" == "on" echo %MAVEN_BATCH_ECHO% + +@REM set %HOME% to equivalent of $HOME +if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%") + +@REM Execute a user defined script before this one +if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre +@REM check for pre script, once with legacy .bat ending and once with .cmd ending +if exist "%USERPROFILE%\mavenrc_pre.bat" call "%USERPROFILE%\mavenrc_pre.bat" %* +if exist "%USERPROFILE%\mavenrc_pre.cmd" call "%USERPROFILE%\mavenrc_pre.cmd" %* +:skipRcPre + +@setlocal + +set ERROR_CODE=0 + +@REM To isolate internal variables from possible post scripts, we use another setlocal +@setlocal + +@REM ==== START VALIDATION ==== +if not "%JAVA_HOME%" == "" goto OkJHome + +echo. +echo Error: JAVA_HOME not found in your environment. >&2 +echo Please set the JAVA_HOME variable in your environment to match the >&2 +echo location of your Java installation. >&2 +echo. +goto error + +:OkJHome +if exist "%JAVA_HOME%\bin\java.exe" goto init + +echo. +echo Error: JAVA_HOME is set to an invalid directory. >&2 +echo JAVA_HOME = "%JAVA_HOME%" >&2 +echo Please set the JAVA_HOME variable in your environment to match the >&2 +echo location of your Java installation. >&2 +echo. +goto error + +@REM ==== END VALIDATION ==== + +:init + +@REM Find the project base dir, i.e. the directory that contains the folder ".mvn". +@REM Fallback to current working directory if not found. + +set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR% +IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir + +set EXEC_DIR=%CD% +set WDIR=%EXEC_DIR% +:findBaseDir +IF EXIST "%WDIR%"\.mvn goto baseDirFound +cd .. +IF "%WDIR%"=="%CD%" goto baseDirNotFound +set WDIR=%CD% +goto findBaseDir + +:baseDirFound +set MAVEN_PROJECTBASEDIR=%WDIR% +cd "%EXEC_DIR%" +goto endDetectBaseDir + +:baseDirNotFound +set MAVEN_PROJECTBASEDIR=%EXEC_DIR% +cd "%EXEC_DIR%" + +:endDetectBaseDir + +IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig + +@setlocal EnableExtensions EnableDelayedExpansion +for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a +@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS% + +:endReadAdditionalConfig + +SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe" +set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar" +set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain + +set WRAPPER_URL="https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.2.0/maven-wrapper-3.2.0.jar" + +FOR /F "usebackq tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO ( + IF "%%A"=="wrapperUrl" SET WRAPPER_URL=%%B +) + +@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central +@REM This allows using the maven wrapper in projects that prohibit checking in binary data. +if exist %WRAPPER_JAR% ( + if "%MVNW_VERBOSE%" == "true" ( + echo Found %WRAPPER_JAR% + ) +) else ( + if not "%MVNW_REPOURL%" == "" ( + SET WRAPPER_URL="%MVNW_REPOURL%/org/apache/maven/wrapper/maven-wrapper/3.2.0/maven-wrapper-3.2.0.jar" + ) + if "%MVNW_VERBOSE%" == "true" ( + echo Couldn't find %WRAPPER_JAR%, downloading it ... + echo Downloading from: %WRAPPER_URL% + ) + + powershell -Command "&{"^ + "$webclient = new-object System.Net.WebClient;"^ + "if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^ + "$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^ + "}"^ + "[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%WRAPPER_URL%', '%WRAPPER_JAR%')"^ + "}" + if "%MVNW_VERBOSE%" == "true" ( + echo Finished downloading %WRAPPER_JAR% + ) +) +@REM End of extension + +@REM If specified, validate the SHA-256 sum of the Maven wrapper jar file +SET WRAPPER_SHA_256_SUM="" +FOR /F "usebackq tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO ( + IF "%%A"=="wrapperSha256Sum" SET WRAPPER_SHA_256_SUM=%%B +) +IF NOT %WRAPPER_SHA_256_SUM%=="" ( + powershell -Command "&{"^ + "$hash = (Get-FileHash \"%WRAPPER_JAR%\" -Algorithm SHA256).Hash.ToLower();"^ + "If('%WRAPPER_SHA_256_SUM%' -ne $hash){"^ + " Write-Output 'Error: Failed to validate Maven wrapper SHA-256, your Maven wrapper might be compromised.';"^ + " Write-Output 'Investigate or delete %WRAPPER_JAR% to attempt a clean download.';"^ + " Write-Output 'If you updated your Maven version, you need to update the specified wrapperSha256Sum property.';"^ + " exit 1;"^ + "}"^ + "}" + if ERRORLEVEL 1 goto error +) + +@REM Provide a "standardized" way to retrieve the CLI args that will +@REM work with both Windows and non-Windows executions. +set MAVEN_CMD_LINE_ARGS=%* + +%MAVEN_JAVA_EXE% ^ + %JVM_CONFIG_MAVEN_PROPS% ^ + %MAVEN_OPTS% ^ + %MAVEN_DEBUG_OPTS% ^ + -classpath %WRAPPER_JAR% ^ + "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" ^ + %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %* +if ERRORLEVEL 1 goto error +goto end + +:error +set ERROR_CODE=1 + +:end +@endlocal & set ERROR_CODE=%ERROR_CODE% + +if not "%MAVEN_SKIP_RC%"=="" goto skipRcPost +@REM check for post script, once with legacy .bat ending and once with .cmd ending +if exist "%USERPROFILE%\mavenrc_post.bat" call "%USERPROFILE%\mavenrc_post.bat" +if exist "%USERPROFILE%\mavenrc_post.cmd" call "%USERPROFILE%\mavenrc_post.cmd" +:skipRcPost + +@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on' +if "%MAVEN_BATCH_PAUSE%"=="on" pause + +if "%MAVEN_TERMINATE_CMD%"=="on" exit %ERROR_CODE% + +cmd /C exit /B %ERROR_CODE% diff --git a/pom.xml b/pom.xml new file mode 100644 index 0000000000..93d754b8ae --- /dev/null +++ b/pom.xml @@ -0,0 +1,248 @@ + + + + 4.0.0 + + dev.morling.demos + average + 1.0.0-SNAPSHOT + + + 21 + true + ${java.version} + UTF-8 + UTF-8 + + + My OSS Project + My Latest OSS Project + 2021 + tbd. + + + + Apache-2.0 + http://www.apache.org/licenses/LICENSE-2.0.txt + repo + + + + + + + org.junit + junit-bom + 5.8.1 + pom + import + + + + + + + org.junit.jupiter + junit-jupiter + test + + + org.assertj + assertj-core + 3.21.0 + test + + + + + + + + + com.mycila + license-maven-plugin + 4.1 + + + net.revelc.code.formatter + formatter-maven-plugin + 2.16.0 + + etc/eclipse-formatter-config.xml + + + + net.revelc.code + impsort-maven-plugin + 1.9.0 + + java.,javax.,org.,com. + true + true + + + + org.apache.maven.plugins + maven-compiler-plugin + 3.8.1 + + true + + + + org.apache.maven.plugins + maven-clean-plugin + 3.1.0 + + + org.apache.maven.plugins + maven-deploy-plugin + 3.0.0-M1 + + + org.apache.maven.plugins + maven-enforcer-plugin + 3.0.0-M3 + + + org.apache.maven.plugins + maven-install-plugin + 3.0.0-M1 + + + org.apache.maven.plugins + maven-jar-plugin + 3.2.0 + + + org.apache.maven.plugins + maven-resources-plugin + 3.2.0 + + + org.apache.maven.plugins + maven-site-plugin + 3.9.1 + + + org.apache.maven.plugins + maven-surefire-plugin + 3.0.0-M5 + + + + + + + + qa + + + !quick + + + + + + com.mycila + license-maven-plugin + +
etc/license.txt
+ true + true + + LICENSE.txt + **/.dontdelete + + + + + + check + + + + + + net.revelc.code.formatter + formatter-maven-plugin + + + format + + format + + process-sources + + + + + + + + + + + + + + + + + + org.apache.maven.plugins + maven-enforcer-plugin + + + enforce-plugin-versions + + enforce + + + + + [${java.version},) + + + true + true + true + clean,deploy,site + + + + + + + + + + + quick + + + quick + + + + true + + + + diff --git a/src/main/java/dev/morling/onebrc/CalculateAverage.java b/src/main/java/dev/morling/onebrc/CalculateAverage.java new file mode 100644 index 0000000000..7672d75087 --- /dev/null +++ b/src/main/java/dev/morling/onebrc/CalculateAverage.java @@ -0,0 +1,44 @@ +/* + * Copyright 2023 The original authors + * + * 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 dev.morling.onebrc; + +import static java.util.stream.Collectors.averagingDouble; +import static java.util.stream.Collectors.groupingBy; + +import java.io.IOException; +import java.nio.file.Files; +import java.nio.file.Paths; +import java.util.Map; +import java.util.TreeMap; +import java.util.stream.Collectors; + +public class CalculateAverage { + + private static final String FILE = "./measurements.txt"; + + public static void main(String[] args) throws IOException { + Map measurements = Files.lines(Paths.get(FILE)) + .limit(10_000_000) + .map(l -> l.split(";")) + .collect(groupingBy(m -> m[0], averagingDouble(m -> Double.parseDouble(m[1])))); + + measurements = new TreeMap<>(measurements.entrySet() + .stream() + .collect(Collectors.toMap(e -> e.getKey(), e -> Math.round(e.getValue() * 10.0) / 10.0))); + + System.out.println(measurements); + } +} diff --git a/src/main/java/dev/morling/onebrc/CreateMeasurements.java b/src/main/java/dev/morling/onebrc/CreateMeasurements.java new file mode 100644 index 0000000000..583c9b1560 --- /dev/null +++ b/src/main/java/dev/morling/onebrc/CreateMeasurements.java @@ -0,0 +1,83 @@ +/* + * Copyright 2023 The original authors + * + * 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 dev.morling.onebrc; + +import java.io.BufferedWriter; +import java.io.File; +import java.io.FileOutputStream; +import java.io.OutputStreamWriter; +import java.util.Arrays; +import java.util.List; +import java.util.concurrent.ThreadLocalRandom; + +public class CreateMeasurements { + + private static final String FILE = "./measurements.txt"; + + private record WeatherStation(String id, double meanTemperature) { + double measurement() { + double m = ThreadLocalRandom.current().nextGaussian(meanTemperature, 10); + return Math.round(m * 10.0) / 10.0; + } + } + + public static void main(String[] args) throws Exception { + long start = System.currentTimeMillis(); + + if (args.length != 1) { + System.out.println("Usage: create_measurements.sh "); + System.exit(1); + } + + int size = 0; + try { + size = Integer.parseInt(args[0]); + } + catch (NumberFormatException e) { + System.out.println("Invalid value for "); + System.out.println("Usage: CreateMeasurements "); + System.exit(1); + } + + List stations = Arrays.asList( + new WeatherStation("auckland", 15.2), + new WeatherStation("concordia", -51.7), + new WeatherStation("lima", 19.2), + new WeatherStation("hamburg", 9.4), + new WeatherStation("hammerfest", 2.7), + new WeatherStation("maui", 15.2), + new WeatherStation("miami", 24.5), + new WeatherStation("nairobi", 17.8), + new WeatherStation("newdelhi", 25.3), + new WeatherStation("tokio", 15.8)); + + File measurements = new File(FILE); + try (FileOutputStream fos = new FileOutputStream(measurements); BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(fos));) { + for (int i = 0; i < size; i++) { + if (i > 0 && i % 50_000_000 == 0) { + System.out.println("Wrote %,d measurements in %s ms".formatted(i, System.currentTimeMillis() - start)); + } + WeatherStation station = stations.get(ThreadLocalRandom.current().nextInt(stations.size())); + bw.write(station.id()); + bw.write(";" + station.measurement()); + bw.newLine(); + } + bw.flush(); + + System.out.println("Created file with %,d measurements in %s ms".formatted(size, System.currentTimeMillis() - start)); + } + } +} diff --git a/src/main/resources/.dontdelete b/src/main/resources/.dontdelete new file mode 100644 index 0000000000..e69de29bb2 diff --git a/src/test/resources/.dontdelete b/src/test/resources/.dontdelete new file mode 100644 index 0000000000..e69de29bb2