Varnish Administration Console

Introduction

The Super Fast Purger(SFP) API acts as the middle agent between your call and all the Varnish Servers that are part of one group. The Vac enables groups to be created and managed, both through an API and a UI.

The workflow of the SuperFast Purger starts with a client issuing a HTTP request containing both the group name and the purge expression. The SFP receives the request, and validates the group name. Once validated and after all the Varnish endpoints are identified, a purge request is constructed and sent out to the Varnish servers.

The Super Fast Purger API is separate from the VAC API for the purpose of high performance purging. It listens on a separate port (8088 by default,can be changed using the jdi_listening_port parameter).

Features

  • Flexible and High Performance - Leverages the speed and flexibility of Varnish Cache.
  • It uses the same syntax as Varnish Cache.
  • Security - HMAC hashing neither password or secret passed over the connection.
  • Fast - We’ve measured more than 60000 req/sec on a 6 core CPU machine.

Configurables

There are configurable items that are specific to the Super Fast Purger. These items are specified in /opt/vac/etc/default file. These default values aims to be high performance out of the box and is inspired from Varnish Cache.

Name Description Default value
jdi_listening_host The listening host for the Super Fast Purger. 0.0.0.0
jdi_listening_port The listening port for the Super Fast Purger. 8088
jdi_client_timeout Client socket timeout. Client being the API user. 5000
jdi_cache_timeout Cache socket timeout. Cache refers to Varnish Cache. This can also be interpreted as worst-case response time from Varnish Cache. 3000
jdi_corepool_size The number of threads to keep in the pool, even if they are idle. 1000
jdi_maxpool_size The maximum number of threads to allow in the pool. 3000
jdi_thread_keepalive When the number of thread is greater than the core, this is the maximum time that excess idle threads will wait for new tasks before terminating. The value here is in minutes. 5
jdi_retries The number of retries the VAC PURGER will attempt. 3
jdi_db_cache_ttl The time-to-live for objects in the db cache used only by the Super Fast Purger. Value here is in ms. 36000000