Gradle RAMdisk ~/.gradle/init.gradle

init.gradle

import org.gradle.internal.os.OperatingSystem

println "Loaded personal ~/.gradle/init.gradle"

final String RAMDiskName = "GradleRamDisk"
final long RAMDiskBytes = 4L * 1024L * 1024L * 1024L // 4Gb

interface RAMDiskManager {                                  
    boolean isReady();
    String getPath();
    void create();
    void drop();                          
}

RAMDiskManager RAMDiskManagerInst = null

switch (OperatingSystem.current()) {
    case OperatingSystem.MAC_OS:
        // inspired by https://stackoverflow.com/questions/29116000/gradle-make-use-of-ramdisk
        RAMDiskManagerInst = new RAMDiskManager() {
            String RAMDiskFSPath = "/Volumes/${RAMDiskName}"
            String RAMDiskDevPath

            boolean isReady() { return new File(RAMDiskFSPath).exists() }

            String getPath() { return RAMDiskFSPath }

            void create() {
                long RAMDiskSectors = RAMDiskBytes / 512L // The sector size is 512 bytes

                RAMDiskDevPath = new ByteArrayOutputStream().withStream { os ->
                    def result = exec {
                        commandLine 'hdiutil', 'attach', '-nomount', "ram://${RAMDiskSectors}"
                        standardOutput os
                    }
                    return os.toString().trim()
                }

                exec {
                    commandLine 'diskutil', 'erasevolume', 'HFS+', RAMDiskName, RAMDiskDevPath
                }
            }

            void drop() {
                exec {
                    commandLine 'diskutil', 'unmountDisk', RAMDiskDevPath
                }
            }
        }
    break
    case OperationSystem.LINUX:
    case OperationSystem.WINDOWS:
        // not implemented yet
    break
}

if (RAMDiskManagerInst != null) {
    gradle.projectsLoaded {
        if (!RAMDiskManagerInst.isReady()) {
            RAMDiskManagerInst.create()
        }

        rootProject.allprojects {
            buildDir = "${RAMDiskManagerInst.getPath()}/gradle-build/${rootProject.name}/${project.name}"
            println "BUILDING TO RAMDISK: buildDir=$buildDir"
        }
    }
} else {
    switch (OperatingSystem.current()) {
        case OperationSystem.LINUX:
            println "RAMDisk optimization not implemented. Check: https://stackoverflow.com/questions/29116000/gradle-make-use-of-ramdisk"
        break
        case OperationSystem.WINDOWS:
            println "RAMDisk optimization not implemented. Check: https://en.wikipedia.org/wiki/List_of_RAM_drive_software#Microsoft_Windows"
        break
    }
}