diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/gatherer.erl | 14 | ||||
| -rw-r--r-- | src/pmon.erl | 13 |
2 files changed, 27 insertions, 0 deletions
diff --git a/src/gatherer.erl b/src/gatherer.erl index 8bce170754..6a71021686 100644 --- a/src/gatherer.erl +++ b/src/gatherer.erl @@ -16,6 +16,20 @@ -module(gatherer). +%% Gatherer is a queue which has producer and consumer processes. Before producers +%% push items to the queue using gatherer:in/2 they need to declare their intent +%% to do so with gatherer:fork/1. When a publisher's work is done, it states so +%% using gatherer:finish/1. +%% +%% Consumers pop messages off queues with gatherer:out/1. If a queue is empty +%% and there are producers that haven't finished working, the caller is blocked +%% until an item is available. If there are no active producers, gatherer:out/1 +%% immediately returns 'empty'. +%% +%% This module is primarily used to collect results from asynchronous tasks +%% running in a worker pool, e.g. when recovering bindings or rebuilding +%% message store indices. + -behaviour(gen_server2). -export([start_link/0, stop/1, fork/1, finish/1, in/2, sync_in/2, out/1]). diff --git a/src/pmon.erl b/src/pmon.erl index a94f5a67af..7981742284 100644 --- a/src/pmon.erl +++ b/src/pmon.erl @@ -16,6 +16,19 @@ -module(pmon). +%% Process Monitor +%% ================ +%% +%% This module monitors processes so that every process has at most +%% 1 monitor. +%% Processes monitored can be dynamically added and removed. +%% +%% Unlike erlang:[de]monitor* functions, this module +%% provides basic querying capability and avoids contacting down nodes. +%% +%% It is used to monitor nodes, queue mirrors, and by +%% the queue collector, among other things. + -export([new/0, new/1, monitor/2, monitor_all/2, demonitor/2, is_monitored/2, erase/2, monitored/1, is_empty/1]). |