[dev] Horde_Ldap performance problem + patch

[Jan Schneider]

Zitat von Xavier Montagutelli <xavier.montagutelli at unilim.fr>:

> Hi list,
>
> I have identified a serious performance problem in the Horde_Ldap module.
>
> When doing a very simple search on a directory with around 50.000 entries,
> getting the results with the "shiftEntry" methods takes a *very* long time,
> compared to using the native PHP functions.
>
> This renders the "listUsers" method in the LDAP auth handler for Horde
> useless.
>
> Some numbers :
>
> 1. Using PHP native LDAP functions
> Number of entries                : 44588
> Search time                      : 2 seconds
> Building list from search result : 1 seconds
>
> 2. Using Horde_Ldap object
> Number of entries                : 44588
> Search time                      : 2 seconds
> Building list from search result : 112 seconds
>
>
> With Xdebug, I have identified the bottleneck. Each call to  
> "shiftEntry" calls
> "count", and this one calls "ldap_count_entries". I suppose this  
> function goes
> through all the remaining results to give the count, so calling it
> inefficient.
>
> With the following patch, it turns to be *much* quicker (~ 6 seconds to build
> the result list).
>
> --- Horde/Ldap/Search.php.orig  2011-08-23 12:41:42.000000000 +0200
> +++ Horde/Ldap/Search.php       2011-08-23 12:45:15.000000000 +0200
> @@ -145,10 +145,6 @@
>       */
>      public function shiftEntry()
>      {
> -        if (!$this->count()) {
> -            return false;
> -        }
> -
>          if (is_null($this->_entry)) {
>              $this->_entry = @ldap_first_entry($this->_link, $this->_search);
>              $entry = Horde_Ldap_Entry::createConnected($this->_ldap, $this-
>> _entry);
>
>
>> From my point of view, the call to "count" is useless, as  
>> ldap_first_entry or
> ldap_next_entry will return false at the end. Or do I miss something ?
>
>
> (BTW, the Net_LDAP2 code suffers from the same problem ...)
>
>
> My code to compare performance is :
>
>
> // Initialisation code
> [...]
> $filter = '(objectclass=inetOrgPerson)';
> $attr = array('uid');
>
> // Methode 1. Using LDAP native functions
> $t0 = time();
> $ldap = ldap_connect($h);
> ldap_bind($ldap, $user, $pass);
> $search = ldap_search ($ldap,
>                 $basedn,
>                 $filter,
>                 $attr);
> $t1 = time();
>
> $userlist = array();
> $entry = ldap_first_entry($ldap, $search);
> while ($entry) {
>    $values = ldap_get_values ($ldap, $entry, 'uid');
>    $userlist[] = $values[0];
>    $entry = ldap_next_entry($ldap, $entry);
> }
> ldap_free_result($search);
> ldap_close($ldap);
> $t2 = time();
>
> echo "1. Using PHP native LDAP functions\n";
> echo "Number of entries                : " . count($userlist) . "\n";
> echo "Search time                      : " . ($t1-$t0) . " seconds\n";
> echo "Building list from search result : " . ($t2-$t1) . " seconds\n";
>
> // Methode 2. Using Horde_Ldap object
> $t0 = time();
> $ldap = new Horde_Ldap(array (
>                 'hostspec' => $h,
>                 'binddn' => $user,
>                 'bindpw' => $pass));
> $search = $ldap->search(
>     $basedn,
>     $filter,
>     array ('attributes' => $attr)
> );
> $t1 = time();
>
> $userlist = array();
> while ($entry = $search->shiftEntry()) {
>     $userlist[] = $entry->getValue('uid', 'single');
> }
> $t2 = time();
>
> echo "2. Using Horde_Ldap object\n";
> echo 'Number of entries                : ' . count($userlist) . "\n";
> echo 'Search time                      : ' . ($t1-$t0) . " seconds\n";
> echo 'Building list from search result : ' . ($t2-$t1) . " seconds\n";

Great analysis! Fixed in Git.

Jan.

-- 
Do you need professional PHP or Horde consulting?
http://horde.org/consulting/