Avoiding deadlocks and small sql improvements

This commit is contained in:
Michael 2016-10-29 20:17:33 +00:00
parent a65479ccfd
commit 7bd79c67a7
4 changed files with 110 additions and 60 deletions

View file

@ -918,7 +918,7 @@ function db_definition($charset) {
"ownerid_created" => array("owner-id","created"),
"wall_body" => array("wall","body(6)"),
"uid_visible_moderated_created" => array("uid","visible","moderated","created"),
"uid_uri" => array("uid","uri"),
"uid_uri" => array("uid", "uri"),
"uid_wall_created" => array("uid","wall","created"),
"resource-id" => array("resource-id"),
"uid_type" => array("uid","type"),

View file

@ -730,6 +730,7 @@ function item_store($arr,$force_parent = false, $notify = false, $dontcache = fa
if ($arr["uid"] == 0) {
$arr["global"] = true;
// Set the global flag on all items if this was a global item entry
q("UPDATE `item` SET `global` = 1 WHERE `uri` = '%s'", dbesc($arr["uri"]));
} else {
$isglobal = q("SELECT `global` FROM `item` WHERE `uid` = 0 AND `uri` = '%s'", dbesc($arr["uri"]));
@ -763,6 +764,17 @@ function item_store($arr,$force_parent = false, $notify = false, $dontcache = fa
return 0;
}
// Check for already added items.
// There is a timing issue here that sometimes creates double postings.
// An unique index would help - but the limitations of MySQL (maximum size of index values) prevent this.
if ($arr["uid"] == 0) {
$r = qu("SELECT `id` FROM `item` WHERE `uri` = '%s' AND `uid` = 0 LIMIT 1", dbesc(trim($arr['uri'])));
if (dbm::is_result($r)) {
logger('Global item already stored. URI: '.$arr['uri'].' on network '.$arr['network'], LOGGER_DEBUG);
return 0;
}
}
// Store the unescaped version
$unescaped = $arr;
@ -777,41 +789,67 @@ function item_store($arr,$force_parent = false, $notify = false, $dontcache = fa
. implode("`, `", array_keys($arr))
. "`) VALUES ('"
. implode("', '", array_values($arr))
. "')" );
. "')");
// And restore it
$arr = $unescaped;
// find the item that we just created
$r = q("SELECT `id` FROM `item` WHERE `uri` = '%s' AND `uid` = %d AND `network` = '%s' ORDER BY `id` ASC",
// When the item was successfully stored we fetch the ID of the item.
if (dbm::is_result($r)) {
$r = q("SELECT LAST_INSERT_ID() AS `item-id`");
if (dbm::is_result($r)) {
$current_post = $r[0]['item-id'];
} else {
// This shouldn't happen
$current_post = 0;
}
} else {
// This can happen - for example - if there are locking timeouts.
logger("Item wasn't stored - we quit here.");
q("COMMIT");
return 0;
}
if ($current_post == 0) {
// This is one of these error messages that never should occur.
logger("couldn't find created item - we better quit now.");
q("COMMIT");
return 0;
}
// How much entries have we created?
// We wouldn't need this query when we could use an unique index - but MySQL has length problems with them.
$r = q("SELECT COUNT(*) AS `entries` FROM `item` WHERE `uri` = '%s' AND `uid` = %d AND `network` = '%s'",
dbesc($arr['uri']),
intval($arr['uid']),
dbesc($arr['network'])
);
if (count($r) > 1) {
// There are duplicates. Keep the oldest one, delete the others
logger('item_store: duplicated post occurred. Removing newer duplicates. uri = '.$arr['uri'].' uid = '.$arr['uid']);
q("DELETE FROM `item` WHERE `uri` = '%s' AND `uid` = %d AND `network` = '%s' AND `id` > %d",
dbesc($arr['uri']),
intval($arr['uid']),
dbesc($arr['network']),
intval($r[0]["id"])
);
q("COMMIT");
return 0;
} elseif (count($r)) {
$current_post = $r[0]['id'];
logger('item_store: created item ' . $current_post);
item_set_last_item($arr);
} else {
logger('item_store: could not locate created item');
if (!dbm::is_result($r)) {
// This shouldn't happen, since COUNT always works when the database connection is there.
logger("We couldn't count the stored entries. Very strange ...");
q("COMMIT");
return 0;
}
if ($r[0]["entries"] > 1) {
// There are duplicates. We delete our just created entry.
logger('Duplicated post occurred. uri = '.$arr['uri'].' uid = '.$arr['uid']);
// Yes, we could do a rollback here - but we are having many users with MyISAM.
q("DELETE FROM `item` WHERE `id` = %d", intval($current_post));
q("COMMIT");
return 0;
} elseif ($r[0]["entries"] == 0) {
// This really should never happen since we quit earlier if there were problems.
logger("Something is terribly wrong. We haven't found our created entry.");
q("COMMIT");
return 0;
}
logger('item_store: created item '.$current_post);
item_set_last_item($arr);
if (!$parent_id || ($arr['parent-uri'] === $arr['uri']))
$parent_id = $current_post;
@ -855,19 +893,6 @@ function item_store($arr,$force_parent = false, $notify = false, $dontcache = fa
);
}
/**
* If this is now the last-child, force all _other_ children of this parent to *not* be last-child
*/
if ($arr['last-child']) {
$r = q("UPDATE `item` SET `last-child` = 0 WHERE `parent-uri` = '%s' AND `uid` = %d AND `id` != %d",
dbesc($arr['uri']),
intval($arr['uid']),
intval($current_post)
);
}
$deleted = tag_deliver($arr['uid'],$current_post);
// current post can be deleted if is for a community page and no mention are
@ -884,19 +909,35 @@ function item_store($arr,$force_parent = false, $notify = false, $dontcache = fa
logger('item_store: new item not found in DB, id ' . $current_post);
}
if ($arr['parent-uri'] === $arr['uri']) {
add_thread($current_post);
} else {
update_thread($parent_id);
}
q("COMMIT");
// Due to deadlock issues with the "term" table we are doing these steps after the commit.
// This is not perfect - but a workable solution until we found the reason for the problem.
create_tags_from_item($current_post);
create_files_from_item($current_post);
// Only check for notifications on start posts
if ($arr['parent-uri'] === $arr['uri']) {
add_thread($current_post);
q("COMMIT");
/**
* If this is now the last-child, force all _other_ children of this parent to *not* be last-child
* It is done after the transaction to avoid dead locks.
*/
if ($arr['last-child']) {
$r = q("UPDATE `item` SET `last-child` = 0 WHERE `parent-uri` = '%s' AND `uid` = %d AND `id` != %d",
dbesc($arr['uri']),
intval($arr['uid']),
intval($current_post)
);
}
if ($arr['parent-uri'] === $arr['uri']) {
add_shadow_thread($current_post);
} else {
update_thread($parent_id);
q("COMMIT");
add_shadow_entry($arr);
}

View file

@ -599,10 +599,10 @@ function notifier_run(&$argv, &$argc){
foreach($r as $rr) {
if((! $mail) && (! $fsuggest) && (! $followup)) {
q("insert into deliverq ( `cmd`,`item`,`contact` ) values ('%s', %d, %d )",
dbesc($cmd),
intval($item_id),
intval($rr['id'])
q("INSERT INTO `deliverq` (`cmd`,`item`,`contact`) VALUES ('%s', %d, %d)
ON DUPLICATE KEY UPDATE `cmd` = '%s', `item` = %d, `contact` = %d",
dbesc($cmd), intval($item_id), intval($rr['id']),
dbesc($cmd), intval($item_id), intval($rr['id'])
);
}
}

View file

@ -115,7 +115,7 @@ function item_post(&$a) {
if(($r === false) || (! count($r))) {
notice( t('Unable to locate original post.') . EOL);
if(x($_REQUEST,'return'))
goaway($a->get_baseurl() . "/" . $return_path );
goaway($return_path);
killme();
}
$parent_item = $r[0];
@ -197,7 +197,7 @@ function item_post(&$a) {
if((x($_REQUEST,'commenter')) && ((! $parent) || (! $parent_item['wall']))) {
notice( t('Permission denied.') . EOL) ;
if(x($_REQUEST,'return'))
goaway($a->get_baseurl() . "/" . $return_path );
goaway($return_path);
killme();
}
@ -209,7 +209,7 @@ function item_post(&$a) {
if((! can_write_wall($a,$profile_uid)) && (! $allow_moderated)) {
notice( t('Permission denied.') . EOL) ;
if(x($_REQUEST,'return'))
goaway($a->get_baseurl() . "/" . $return_path );
goaway($return_path);
killme();
}
@ -339,7 +339,7 @@ function item_post(&$a) {
killme();
info( t('Empty post discarded.') . EOL );
if(x($_REQUEST,'return'))
goaway($a->get_baseurl() . "/" . $return_path );
goaway($return_path);
killme();
}
}
@ -756,7 +756,7 @@ function item_post(&$a) {
if(x($datarray,'cancel')) {
logger('mod_item: post cancelled by plugin.');
if($return_path) {
goaway($a->get_baseurl() . "/" . $return_path);
goaway($return_path);
}
$json = array('cancel' => 1);
@ -795,7 +795,7 @@ function item_post(&$a) {
proc_run(PRIORITY_HIGH, "include/notifier.php", 'edit_post', $post_id);
if((x($_REQUEST,'return')) && strlen($return_path)) {
logger('return: ' . $return_path);
goaway($a->get_baseurl() . "/" . $return_path );
goaway($return_path);
}
killme();
} else
@ -877,17 +877,26 @@ function item_post(&$a) {
intval($datarray['visible'])
);
$r = q("SELECT `id` FROM `item` WHERE `uri` = '%s' LIMIT 1",
dbesc($datarray['uri']));
if(!count($r)) {
if (dbm::is_result($r)) {
$r = q("SELECT LAST_INSERT_ID() AS `item-id`");
if (dbm::is_result($r)) {
$post_id = $r[0]['item-id'];
} else {
$post_id = 0;
}
} else {
logger('mod_item: unable to create post.');
$post_id = 0;
}
if ($post_id == 0) {
q("COMMIT");
logger('mod_item: unable to retrieve post that was just stored.');
notice( t('System error. Post not saved.') . EOL);
goaway($a->get_baseurl() . "/" . $return_path );
notice(t('System error. Post not saved.') . EOL);
goaway($return_path);
// NOTREACHED
}
$post_id = $r[0]['id'];
logger('mod_item: saved item ' . $post_id);
$datarray["id"] = $post_id;
@ -1070,7 +1079,7 @@ function item_post_return($baseurl, $api_source, $return_path) {
return;
if($return_path) {
goaway($baseurl . "/" . $return_path);
goaway($return_path);
}
$json = array('success' => 1);