boinc/doc/backend_logic.php

144 lines
4.7 KiB
PHP

<?
require_once("docutil.php");
page_head("Backend program logic");
echo "
<h3>Work generator</h3>
<p>
<pre>
for each wu created
wu.transition_time = now
</pre>
<h3>scheduler</h3>
<pre>
when send a result
result.report_deadline = now + wu.delay_bound
wu.transition_time = min(wu.transition_time, result.report_deadline)
when receive a result
if client error
result.outcome = client_error
result.validate_state = INVALID
else
result.outcome = success
result.server_state = OVER
wu.transition_time = now
when a result falls off the bottom of infeasible queue
result.server_state = OVER
result.outcome = COULDNT_SEND
wu.transition_time = now
</pre>
<h3>Transitioner</h3>
<p>
<pre>
// gets run when either
// - a result becomes done (via timeout or client reply)
// - the WU error mask is set (e.g. by validater)
// - assimilation is finished
for each WU with now > transition_time:
// check for timed-out results
for each result of WU
if result.server_state = in_progress and now > result.report_deadline
result.server_state = OVER
result.outcome = NO_REPLY
// trigger validation if needed
K = # of SUCCESS results
if K >= M
if any result is server_state OVER, outcome SUCCESS, validate_state INIT
wu.need_validate = true
// check for WU error conditions
if any result has outcome couldnt_send
error_mask |= couldnt_send
K = # results with outcome = client_error
if K > A
error_mask |= too_many_error_results
// Note: check on # of success results is done in validator
K = total # results
if K > B
error_mask |= too_many_total_results
// if no WU errors, generate new results if needed
if error_mask == 0
K = # results w/ server_state = unsent or in_progress
L = N - K
generate L new results
// if WU errors, clean up unsent results
// and trigger assimilation if needed
if error_mask
for all results server_state = unsent
server_state = over
outcome = didnt_need
if wu.assimilate_state == init
wu.assimilate_state = ready
// if WU is assimilated, trigger deletion of files
if wu.assimilated_state = DONE
// trigger input file deletion if needed
if all results are OVER
wu.file_delete_state = ready
// outputs of error results can be deleted immediately;
// outputs of successful results can be deleted when validated
for results of WU
if canonical result and not all results OVER
continue
if outcome = CLIENT_ERROR or (SUCCESS and (VALID or INVALID))
if file_delete_state = INIT
result.file_delete_state = READY
// get next result timeout if any
transition_time = MAX_INT
for all results IN_PROGRESS
transition_time = min(transition_time, result.report_deadline)
</pre>
<h3>Validator</h3>
<pre>
for each WU w/ need_validate true
if have canonical result
for each result w/ validate_state INIT and outcome SUCCESS
// possible that we've already deleted canonical output files
if canonical_result.file_delete_state = DONE
validate_state = INVALID
else
if matches canonical, grant credit
validate_state = VALID or INVALID
need_to_handle_over_results = true
else
S = set of results w/ outcome SUCCESS
if consensus(S)
set canonical_result
set success results as VALID or INVALID
grant credit
need_to_handle_over_results = true
wu.assimilate_state = READY
for all results server_state UNSENT
server_state = OVER
outcome = DIDNT_NEED
else
if # of successful results > C
wu.error_mask |= too_many_success_result
need_to_handle_over_results = true
if need_to_handle_over_results:
wu.transition_time = now
</pre>
<h3>Assimilator</h3>
<pre>
for each WU with assimilate_state = READY
call project-specific handler function
wu.assimilate_state = done
wu.transition_time = now
</pre>
";
page_tail();
?>