From 8920afaf2fb1d0b724f9528d009c0bc226c3adbc Mon Sep 17 00:00:00 2001 From: Kim Alvefur Date: Sun, 6 Dec 2015 02:09:52 +0100 Subject: mod_blocklist: Expand comments on caching of blocklists --- plugins/mod_blocklist.lua | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/plugins/mod_blocklist.lua b/plugins/mod_blocklist.lua index add7abb3..a38d2a0f 100644 --- a/plugins/mod_blocklist.lua +++ b/plugins/mod_blocklist.lua @@ -19,11 +19,17 @@ local jid_split = require"util.jid".split; local storage = module:open_store(); local sessions = prosody.hosts[module.host].sessions; --- Cache of blocklists by username may randomly expire at any time +-- First level cache of blocklists by username. +-- Weak table so may randomly expire at any time. local cache = setmetatable({}, { __mode = "v" }); --- Second level of caching, keeps a fixed number of items, --- also anchors items in the above cache +-- Second level of caching, keeps a fixed number of items, also anchors +-- items in the above cache. +-- +-- The size of this affects how often we will need to load a blocklist from +-- disk, which we want to avoid during routing. On the other hand, we don't +-- want to use too much memory either, so this can be tuned by advanced +-- users. TODO use science to figure out a better default, 64 is just a guess. local cache_size = module:get_option_number("blocklist_cache_size", 64); local cache2 = require"util.cache".new(cache_size); -- cgit v1.2.3