<?php
require_once("docutil.php");
page_head("Trickle message implementation");
echo "
<p>
On the client,
<code>boinc_send_trickle_up()</code>
creates a file 'trickle_up' in the slot directory
and signals the core client via shared memory.
When the core client gets this signal,
or when the application exits,
it moves the file from 'slot/trickle'
to 'project/trickle_up_resultid_time'.
<p>
When the core client sends an RPC to a server,
it scans the project directory for these trickle-up files
includes them in the request,
and appends '.sent' to their filenames.
On successful RPC completion it deletes trickle-up files
that were sent earlier.

<p>
On the server,
messages are stored in database tables 'trickle_up' and 'trickle_down'.
The scheduling server extracts trickle messages from
the request message and inserts them in the trickle_up table.
If the 'trickle_down' flag in the configuration is set,
it scans the database for trickle-down messages for this host
and includes them in the reply message,
clearing the 'handled' flag in the DB record.

<p>
The client parses trickle-down messages
in the scheduler reply,
creates files of the form trickle_down_createtime_id
in the slot directory,
and signals the app via shared memory that a message is available.

";
page_tail();
?>