From 3fb3e862280b90a743ac99ff044535b90ed2f4c0 Mon Sep 17 00:00:00 2001 From: Kim Alvefur Date: Sat, 20 Nov 2021 19:23:08 +0100 Subject: mod_csi_simple: Allow some straggler traffic after flushing buffer Statistics from my server shows a high rate of very short buffer hold times, most of which are the result of replies to pings or other iq traffic, or mod_smacks acks and ack requests just after a flush was completed. This grace period should eliminate noise and quick flipping between flushing and inactive mode. --- plugins/mod_csi_simple.lua | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) (limited to 'plugins/mod_csi_simple.lua') diff --git a/plugins/mod_csi_simple.lua b/plugins/mod_csi_simple.lua index 3fbdf314..a727f427 100644 --- a/plugins/mod_csi_simple.lua +++ b/plugins/mod_csi_simple.lua @@ -10,8 +10,10 @@ local jid = require "util.jid"; local st = require "util.stanza"; local dt = require "util.datetime"; local filters = require "util.filters"; +local timer = require "util.timer"; local queue_size = module:get_option_number("csi_queue_size", 256); +local resume_delay = module:get_option_number("csi_resume_inactive_delay", 5); local important_payloads = module:get_option_set("csi_important_payloads", { }); @@ -194,15 +196,30 @@ module:hook("pre-resource-unbind", function (event) disable_optimizations(session); end, 1); -module:hook("c2s-ondrain", function (event) - local session = event.session; - if (session.state == "flushing" or session.state == "inactive") and session.conn and session.conn.pause_writes then +local function resume_optimizations(_, _, session) + if (session.state == "flushing" or session.state == "inactive") and session.conn and session.conn.pause_writes then session.state = "inactive"; session.conn:pause_writes(); session.csi_measure_buffer_hold = measure_buffer_hold(); session.log("debug", "Buffer flushed, resuming inactive mode (queue size was %d)", session.csi_counter); session.csi_counter = 0; end + session.csi_resume = nil; +end + +module:hook("c2s-ondrain", function (event) + local session = event.session; + if (session.state == "flushing" or session.state == "inactive") and session.conn and session.conn.pause_writes then + -- After flushing, remain in pseudo-flushing state for a moment to allow + -- some followup traffic, iq replies, smacks acks to be sent without having + -- to go back and forth between inactive and flush mode. + if not session.csi_resume then + session.csi_resume = timer.add_task(resume_delay, resume_optimizations, session); + end + -- Should further noise in this short grace period push back the delay? + -- Probably not great if the session can be kept in pseudo-active mode + -- indefinitely. + end end); function module.load() -- cgit v1.2.3