Configuration

Configure the PDFSamurai Docker Server using environment variables passed to docker run.

Environment variables

Variable	Default	Description
PORT	3000	Server port
WORKERS	1	Number of worker threads for PDF generation
MAX_QUEUE_SIZE	100	Maximum queued requests before the server returns 503
TASK_TIMEOUT	60000	PDF generation timeout in milliseconds

Example

docker run -p 3000:3000 \
  -e WORKERS=4 \
  -e MAX_QUEUE_SIZE=200 \
  -e TASK_TIMEOUT=30000 \
  pdfsamurai/server

Scaling workers

By default, the server runs with a single worker. This is the safest option and works on any machine. If you need higher throughput, increase the number of workers based on your setup.

Dedicated server

Use all CPUs minus one (reserves a CPU for the main thread):

docker run -p 3000:3000 \
  -e WORKERS=$(( $(nproc) - 1 )) \
  pdfsamurai/server

Shared server

Use half the CPUs to leave resources for other services:

docker run -p 3000:3000 \
  -e WORKERS=$(( $(nproc) / 2 )) \
  pdfsamurai/server

Fixed value

Set a specific number of workers:

docker run -p 3000:3000 \
  -e WORKERS=4 \
  pdfsamurai/server

Memory considerations

Each worker starts with approximately 64 MB of memory and can grow up to 2 GB depending on template complexity. Make sure you have enough RAM for the number of workers you configure.

More workers than available CPU cores will not improve throughput and may slow down individual PDF generation.