Memory optimisations using jemalloc and tcmalloc on Linux

glibc-tuning.sh

#!/bin/sh

# touch /etc/profile.d/malloc_config.sh

# Get total RAM size in MB
total_ram=$(free -m | awk '/^Mem:/{print $2}')

if [ "$total_ram" -lt 8192 ]; then
    # Low RAM settings
    export MALLOC_ARENA_MAX=2
    export MALLOC_MMAP_THRESHOLD_=65536  # 64 KB
    export MALLOC_TRIM_THRESHOLD_=131072  # 128 KB
    export MALLOC_TOP_PAD_=32768  # 32 KB
elif [ "$total_ram" -lt 32768 ]; then
    # Moderate RAM settings
    export MALLOC_ARENA_MAX=4
    export MALLOC_MMAP_THRESHOLD_=131072  # 128 KB
    export MALLOC_TRIM_THRESHOLD_=262144  # 256 KB
    export MALLOC_TOP_PAD_=65536  # 64 KB
elif [ "$total_ram" -lt 65536 ]; then
    # High RAM settings
    export MALLOC_ARENA_MAX=6
    export MALLOC_MMAP_THRESHOLD_=196608  # 192 KB
    export MALLOC_TRIM_THRESHOLD_=393216  # 384 KB
    export MALLOC_TOP_PAD_=98304  # 96 KB
else
    # Highest RAM settings
    export MALLOC_ARENA_MAX=8
    export MALLOC_MMAP_THRESHOLD_=262144  # 256 KB
    export MALLOC_TRIM_THRESHOLD_=524288  # 512 KB
    export MALLOC_TOP_PAD_=131072  # 128 KB
fi

export MALLOC_MMAP_MAX_=65536
export MALLOC_CHECK_=0
export MALLOC_PERTURB_=0


# sudo chmod +x /etc/profile.d/malloc_config.sh

jemalloc-centos.sh

#!/bin/bash

# Update package lists
sudo yum update -y

# Install dependencies
sudo yum groupinstall -y "Development Tools"
sudo yum install -y autoconf automake libtool

# Download jemalloc source code
JEMALLOC_VERSION=5.3.0
wget https://github.com/jemalloc/jemalloc/releases/download/${JEMALLOC_VERSION}/jemalloc-${JEMALLOC_VERSION}.tar.bz2

# Extract the downloaded tarball
tar -xvf jemalloc-${JEMALLOC_VERSION}.tar.bz2

# Change to the extracted directory
cd jemalloc-${JEMALLOC_VERSION}

# Compile and install jemalloc
./autogen.sh
make
sudo make install

jemalloc-check-usage.sh

grep -z 'LD_PRELOAD' /proc/<pid>/environ | tr '\0' '\n'


# if jemalloc is listed among the loaded libraries for a process.
lsof -p <pid> | grep jemalloc

# to list the shared libraries used by an executable
ldd /path/to/your/application | grep jemalloc

jemalloc-mysql.sh

# Create a systemd override directory for MySQL
sudo mkdir -p /etc/systemd/system/mysql.service.d

# Create a systemd override file for MySQL
echo -e "[Service]\nEnvironment=\"LD_PRELOAD=/usr/local/lib/libjemalloc.so\"\nEnvironment=\"MALLOC_CONF='dirty_decay_ms:1000,narenas:2,background_thread:true'\"" | sudo tee /etc/systemd/system/mysqld.service.d/override.conf

# Reload systemd and restart MySQL
sudo systemctl daemon-reload
sudo systemctl restart mysql 

jemalloc-os.sh

# Set jemalloc as the default allocator and MALLOC_ARENA_MAX=2 at the OS level
echo 'export LD_PRELOAD=/usr/local/lib/libjemalloc.so' | sudo tee -a /etc/profile.d/jemalloc.sh
echo "export MALLOC_CONF='dirty_decay_ms:1000,narenas:2,background_thread:true'" | sudo tee -a /etc/profile.d/jemalloc.sh

# Make the script executable
sudo chmod +x /etc/profile.d/jemalloc.sh

# Apply the environment variables immediately
source /etc/profile.d/jemalloc.sh

jemalloc-pg.sh

# Create a systemd override directory for PostgreSQL
sudo mkdir -p /etc/systemd/system/postgresql.service.d

# Create a systemd override file for PostgreSQL
echo -e "[Service]\nEnvironment=\"LD_PRELOAD=/usr/local/lib/libjemalloc.so\"\nEnvironment=\"MALLOC_CONF='dirty_decay_ms:1000,narenas:2,background_thread:true'\"" | sudo tee /etc/systemd/system/postgresql.service.d/override.conf

# Reload systemd and restart PostgreSQL
sudo systemctl daemon-reload
sudo systemctl restart postgresql

jemalloc-terminal.sh

# Add LD_PRELOAD to .bashrc
echo 'export LD_PRELOAD=/usr/local/lib/libjemalloc.so' >> ~/.bashrc
echo "export MALLOC_CONF='dirty_decay_ms:1000,narenas:2,background_thread:true'" >> ~/.bashrc

# Reload .bashrc to apply changes
source ~/.bashrc

# Add LD_PRELOAD to .bashrc
echo 'export LD_PRELOAD=/usr/local/lib/libjemalloc.so' >> ~/.zshrc
echo "export MALLOC_CONF='dirty_decay_ms:1000,narenas:2,background_thread:true'" >> ~/.zshrc

# Reload .zshrc to apply changes
source ~/.zshrc

jemalloc.sh

#!/bin/bash

# Update package lists
sudo apt-get update
sudo apt-get upgrade

# Install dependencies
sudo apt-get install -y autoconf automake libtool make gcc

# Download jemalloc source code
JEMALLOC_VERSION=5.3.0
wget https://github.com/jemalloc/jemalloc/releases/download/${JEMALLOC_VERSION}/jemalloc-${JEMALLOC_VERSION}.tar.bz2

# Extract the downloaded tarball
tar -xvf jemalloc-${JEMALLOC_VERSION}.tar.bz2

# Change to the extracted directory
cd jemalloc-${JEMALLOC_VERSION}

# Compile and install jemalloc
./autogen.sh
make
sudo make install

tcmalloc-global.sh

#!/bin/bash

# Install TCMalloc
sudo apt-get update
sudo apt-get install -y google-perftools

# Get total RAM in KB
total_ram_kb=$(grep MemTotal /proc/meminfo | awk '{print $2}')
# Convert total RAM to GB
total_ram_gb=$((total_ram_kb / 1024 / 1024))

# Set default values for different RAM configurations
if [ $total_ram_gb -le 8 ]; then
    large_alloc_threshold=33554432  # 32 MB
    max_total_thread_cache_bytes=67108864  # 64 MB
    aggressive_decommit=true
    transfer_batch_size=32
elif [ $total_ram_gb -le 16 ]; then
    large_alloc_threshold=67108864  # 64 MB
    max_total_thread_cache_bytes=268435456  # 256 MB
    aggressive_decommit=true
    transfer_batch_size=64
elif [ $total_ram_gb -le 32 ]; then
    large_alloc_threshold=100663296  # 96 MB
    max_total_thread_cache_bytes=536870912  # 512 MB
    aggressive_decommit=true
    transfer_batch_size=64
else
    large_alloc_threshold=134217728  # 128 MB
    max_total_thread_cache_bytes=1073741824  # 1 GB
    aggressive_decommit=true
    transfer_batch_size=128
fi

# Export environment variables
echo "Setting TCMalloc parameters based on ${total_ram_gb}GB RAM..."
export LD_PRELOAD="/usr/lib/libtcmalloc.so"
export TCMALLOC_LARGE_ALLOC_REPORT_THRESHOLD=$large_alloc_threshold
export TCMALLOC_MAX_TOTAL_THREAD_CACHE_BYTES=$max_total_thread_cache_bytes
export TCMALLOC_AGGRESSIVE_DECOMMIT=$aggressive_decommit
export TCMALLOC_TRANSFER_BATCH_SIZE=$transfer_batch_size

# Add to /etc/profile for global settings
echo "export LD_PRELOAD='/usr/lib/libtcmalloc.so'" | sudo tee -a /etc/profile
echo "export TCMALLOC_LARGE_ALLOC_REPORT_THRESHOLD=$large_alloc_threshold" | sudo tee -a /etc/profile
echo "export TCMALLOC_MAX_TOTAL_THREAD_CACHE_BYTES=$max_total_thread_cache_bytes" | sudo tee -a /etc/profile
echo "export TCMALLOC_AGGRESSIVE_DECOMMIT=$aggressive_decommit" | sudo tee -a /etc/profile
echo "export TCMALLOC_TRANSFER_BATCH_SIZE=$transfer_batch_size" | sudo tee -a /etc/profile

very helpful script

To make sure you are using the correct path for your jemalloc lib file one can use

find /usr -name "libjemalloc.so*"