How to Compile FFmpeg with Jemalloc or Tcmalloc

This article provides a practical, step-by-step guide on how to compile FFmpeg using custom memory allocators like jemalloc or tcmalloc instead of the standard glibc allocator. By integrating these high-performance allocators, you can significantly reduce memory fragmentation and improve execution speed in multi-threaded video encoding and decoding environments.

Why Use Custom Allocators with FFmpeg?

FFmpeg is highly multi-threaded, especially when handling multiple concurrent video streams or complex filtergraphs. The default system allocator (ptmalloc in glibc) can suffer from memory fragmentation and lock contention under high concurrency.

Jemalloc (developed by FreeBSD and used by Facebook) excels at reducing fragmentation and scaling across multiple CPU cores.
Tcmalloc (Thread-Caching Malloc, developed by Google) is optimized for high-concurrency workloads with low overhead per thread.

Step 1: Install the Custom Allocator

Before configuring FFmpeg, you must install the development headers and libraries for your chosen allocator.

On Ubuntu/Debian:

For jemalloc:

sudo apt-get update
sudo apt-get install libjemalloc-dev

For tcmalloc:

sudo apt-get update
sudo apt-get install libgoogle-perftools-dev

On CentOS/RHEL/Rocky Linux:

For jemalloc:

sudo dnf install epel-release
sudo dnf install jemalloc-devel

For tcmalloc:

sudo dnf install epel-release
sudo dnf install gperftools-devel

Step 2: Configure FFmpeg

Clone the FFmpeg source repository and navigate to the directory:

git clone https://git.ffmpeg.org/ffmpeg.git ffmpeg
cd ffmpeg

To compile FFmpeg with the custom allocator, you must pass the appropriate compiler and linker flags to the ./configure script using the --extra-libs option. This ensures the allocator is statically or dynamically linked directly into the binary.

Option A: Configuring with Jemalloc

./configure \
  --enable-gpl \
  --enable-nonfree \
  --extra-libs="-ljemalloc"

Option B: Configuring with Tcmalloc

./configure \
  --enable-gpl \
  --enable-nonfree \
  --extra-libs="-ltcmalloc_minimal"

(Note: Using tcmalloc_minimal is recommended for FFmpeg because it contains the memory allocation routines without the overhead of the CPU and heap profilers).

Step 3: Compile and Install

Once the configuration process completes successfully, compile the binaries using all available CPU cores:

make -j$(nproc)
sudo make install

Step 4: Verify the Build

To confirm that FFmpeg successfully linked against your custom allocator, use the ldd command on the compiled binary:

ldd $(which ffmpeg)

Look for the corresponding library in the output:

For jemalloc, you should see: libjemalloc.so => /lib/x86_64-linux-gnu/libjemalloc.so
For tcmalloc, you should see: libtcmalloc_minimal.so => /lib/x86_64-linux-gnu/libtcmalloc_minimal.so