[TS-4099] Replace XML statistics with Lua

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 6.2.0
• Component/s: Lua, Manager, Metrics
• Assignee: James Peach
• Reporter: James Peach
• Created: 25/Dec/15 20:03
• Updated: 19/Jul/16 20:16
• Resolved: 22/Jan/16 03:28

Description

The custom metrics XML format is undocumented and difficult to use and extend. Since we plan to use Lua for configuration programmability, lets make a start by replacing this subsystem with Lua.

It turns out that Lua is mostly more readable and easier to understand. Performance is roughly similar.

Example syntax:

float 'proxy.node.user_agent_total_bytes_avg_10s' [[
  local self = ...

  return interval_delta_of_10s(self, function()
    return proxy.node.user_agent_total_bytes
  end)
]]

counter 'proxy.node.origin_server_total_bytes' [[
  return proxy.node.http.origin_server_total_request_bytes +
    proxy.node.http.origin_server_total_response_bytes +
    proxy.node.http.parent_proxy_total_request_bytes +
    proxy.node.http.parent_proxy_total_response_bytes
]]

Issue Links

• blocks: TS-4100 Remove XML statistics
• depends upon: TS-4119 LuaJIT and ASAN do not work well together
• is related to: TS-4107 proxy.process.ssl.total_success_handshake_count_in has wrong record type
• relates to: TS-3830 Metrics created via stats.config.xml should not need to be registered in RecordsConfig.cc
• relates to: TS-3686 Implement Lua "scriptlets", as discussed at the Austin 2015 Summit
• relates to: TS-3183 Clean up (and/or eliminate?) some proxy.node metrics