Skip to content
WarpDL

Advanced Features

WarpDL includes several advanced features for optimizing download performance and flexibility.

Background Downloads

Section titled “Background Downloads”

Run downloads in the background without blocking your terminal:

Terminal window
warpdl download --background https://example.com/large-file.zip

The download starts immediately and returns control to your terminal. Use attach to reconnect:

Terminal window
warpdl list -p          # Find the download hash
warpdl attach <hash>    # Reconnect to view progress

Environment Variable

Section titled “Environment Variable”
Terminal window
export WARPDL_BACKGROUND=1  # Not yet implemented, use --background flag

Speed Limiting

Section titled “Speed Limiting”

Limit download speed to avoid saturating your network:

Terminal window
warpdl download --speed-limit 1MB https://example.com/file.zip
warpdl download -S 512KB https://example.com/file.zip

Supported units:

  • B - Bytes per second
  • KB - Kilobytes per second
  • MB - Megabytes per second
  • 0 - Unlimited (default)

Environment Variable

Section titled “Environment Variable”
Terminal window
export WARPDL_SPEED_LIMIT=1MB

Work Stealing

Section titled “Work Stealing”

Work stealing is an optimization where faster download segments “steal” remaining work from slower segments. This maximizes bandwidth utilization when some connections are slower than others.

Enabled by default. To disable:

Terminal window
warpdl download --no-work-steal https://example.com/file.zip

How It Works

Section titled “How It Works”
  1. File is split into segments (default: up to 200 parts)
  2. Each segment downloads in parallel
  3. When a fast segment completes, it takes over a portion of the slowest segment’s remaining range
  4. This continues until the entire file is downloaded

When to Disable

Section titled “When to Disable”
  • When downloading from servers that don’t handle range requests well
  • When you want predictable segment boundaries
  • When debugging download issues

Environment Variable

Section titled “Environment Variable”
Terminal window
export WARPDL_NO_WORK_STEAL=1

Checksum Validation

Section titled “Checksum Validation”

WarpDL automatically validates downloads when the server provides checksums:

  • Content-MD5 header
  • Digest header (SHA-256, SHA-512)

If validation fails, the download is marked as corrupted and you’ll be notified.

Debug Logging

Section titled “Debug Logging”

Enable verbose logging for troubleshooting:

Terminal window
warpdl download --debug https://example.com/file.zip

Or globally:

Terminal window
export WARPDL_DEBUG=1

Debug output includes:

  • HTTP request/response details
  • Segment allocation decisions
  • Work stealing events
  • Retry attempts and errors

Default Download Directory

Section titled “Default Download Directory”

Set a default download location:

Terminal window
export WARPDL_DEFAULT_DL_DIR=~/Downloads

When set, downloads go to this directory unless overridden with --download-path.