use android gradle plugin 3.0.0 is slower than gradle plugin 2.3.3 - gradle

Question

when update the com.android.tools.build:gradle:2.2.3 to com.android.tools.build:gradle:3.0.0 , and I find the build-time is longer than 2.3.3 .
the root build.gradle is
buildscript {
repositories {
google()
mavenCentral()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.0.0'
}
}
the app/build.gradle is here , and all my dependencies use compile
apply plugin: 'com.android.application'
android {
sourceSets {
main {
...
}
}
dexOptions {
preDexLibraries = false
incremental true
javaMaxHeapSize "8g"
keepRuntimeAnnotatedClasses false
}
lintOptions {
abortOnError false
checkReleaseBuilds false
}
packagingOptions {
exclude 'META-INF/DEPENDENCIES'
exclude 'META-INF/LICENSE'
exclude 'META-INF/LICENSE.txt'
exclude 'META-INF/license.txt'
exclude 'META-INF/NOTICE'
exclude 'META-INF/NOTICE.txt'
exclude 'META-INF/notice.txt'
exclude 'META-INF/ASL2.0'
exclude 'org/apache/commons/codec/language/bm/*.txt'
}
compileSdkVersion 24
buildToolsVersion "27.0.1"
}
defaultConfig {
applicationId "com.gg.kk"
minSdkVersion 15
targetSdkVersion 23
versionCode 512654
versionName "version"
multiDexEnabled true
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:multidex:1.0.1'
.... many dependencies ....
}
can anyone tell me why my build become slow?

Answer 1

Many different things can effect gradle build times.
To decrease this time you may want to try at least one of this solutions:
Check if Gradle Deamon is enabled. It should be enabled by default.
Keep your Gradle up-to-date (You are already good at this though)
you can go /gradle/wrapper/gradle-wrapper.properties and upgrade gradle version by changing distributionUrl
Increase your heapsize
org.gradle.jvmargs=-Xmx3072m -XX:MaxPermSize=512m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8
Enable parallelism in your gradle.properties by adding org.gradle.parallel=true
Don't use dynamic dependencies like compile 'com.android.support:appcompat-v7:27.+'
File -> Settings -> Build, Execution, Deployment -> Build Tools -> Gradle
Check the 'Offline work' under 'Global Gradle settings' Short term solution.
Check this https://developer.android.com/studio/build/optimize-your-build.html