Skip to main content

A simple, fast, pure-python load balancer

Project description

PumpkinLB is a fast multi-process TCP load balancer / port forwarder, compatible with: Linux, Cygwin, and Windows environments. It listens for requests on ports local to the machine on which it is running, and farms them out to any number of workers. You can use it to very quickly setup a load balancer, e.x. from 1 entry-point to 5 different apache servers.

Each incoming port is waited-on by a distinct process, and each connection is yet another process, thus it performs very well even under heavy load. Usage

Execute by running [cfgFile]

Where cfgFile is the path to your config file. There is a sample “example.cfg” included.

Config file is broken up into sections, definable by [$SectionName], followed by variables in format of key=value.


pre_resolve_workers=0/1 [Default 1] Any workers defined with a hostname will be evaluated at the time the config is read.
This is preferable as it saves a DNS trip for every request, and should be enabled
unless your DNS is likely to change and you want the workers to match the change.

localaddr:inport=worker1:port,worker2:port… Listen on interface defined by “localaddr” on port “inport”. Farm out to worker addresses and ports. Ex:,
inport=worker1:port,worker2:port… Listen on all interfaces on port “inport”, and farm out to worker addresses with given ports. Ex: 80=,

So an example to listen on port 80 localhost and farm out to 3 apache servers on your local subnet:


Sending SIGTERM, SIGINT, or pressing control+c will do a graceful shutdown (it will wait for up to 4 seconds to finish any active requests, and then terminate).

Requests are generally handled round-robin between the various workers. If a request fails on a backend worker, it will be retried on another random worker until it succeeds, and a message will be logged.

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for PumpkinLB, version 1.2.1
Filename, size File type Python version Upload date Hashes
Filename, size PumpkinLB-1.2.1.tar.gz (7.0 kB) File type Source Python version None Upload date Hashes View

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring DigiCert DigiCert EV certificate Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page