prepare eks node for running java asyc profiler

prepare_eks_node.sh

#!/bin/bash

set -a # export all functions
set -e
set -o pipefail

me=`basename "$0"`
date_fmt='+%Y-%m-%d %H:%M:%S %z'

export version=${JA_PRF_VERSION:-'2.9'}
export async_profiler_tarball_url="https://github.com/jvm-profiling-tools/async-profiler/releases/download/v${version}/async-profiler-${version}-linux-x64.tar.gz"
export workdir=${JA_PRF_WORKDIR:-'/tmp'}

export host=`hostname`
# functions ====================================================================

function log() {
    echo "`date "$date_fmt"` [${me}@${host}] ${1}"
}

function die() {
    local msg=${1:-"ERROR: die for reason unknown"}
    local code=${2:-254}

    log "${msg}" >&2
    exit ${code}
}


function setup_sysctl() {
    log " ... setup sysctl params"
    # https://github.com/async-profiler/async-profiler#basic-usage
    sysctl kernel.perf_event_paranoid=1 || die "ERROR: failed to set_prerequisites" 11
    sysctl kernel.kptr_restrict=0       || die "ERROR: failed to set_prerequisites" 12
    log "[ok] setup sysctl params"
}

function setup_java() {
    log " ... setup java"
    ( which java || yum install -y java ) && java --version || die "ERROR: java is required" 13
    log "[ok] setup java"
}

function setup_java_async_profiler() {
    log " ... setup java async profiler: ${workdir}"
    mkdir -p ${workdir}

    if [ ! -d "${workdir}/async-profiler-${version}-linux-x64" ]; then
        log " ... download java async profiler package: ${async_profiler_tarball_url} "
        curl -LsSf "${async_profiler_tarball_url}" | tar -xz -C ${workdir}
    else
        log " ... java async profiler package found: ${workdir}/async-profiler-${version}-linux-x64"
    fi
    log "[ok] setup java async profiler"
}

function setup_node() {
    setup_sysctl
    setup_java
    setup_java_async_profiler
}

# main ====================================================================

setup_node