I've done some minor hacks on zp to boost performance. I'm using eAccelerator with PHP-FastCGI, but these hacks can easily be ported to APC, XCache or even memcached. Alternatively, you may also use disk-based caching.

[b]#1 Reduce load on the DB server:[/b]
This is based on the caching technique described on http://www.zenphoto.org/2008/01/hacks/ We'll use eAccelerator shm cache instead of storing the query results on disk.

• Edit the functions-db.php under zp-core directory.
• Search function query_single_row, change it to:
  `

function query_single_row($sql, $noerrmsg=false) {

if ($cache = get_cache($sql))

    return $cache;

$result = query($sql, $noerrmsg);

if ($result) {

    $data = mysql_fetch_assoc($result);

    store_cache($sql, $data);

    return $data;

}

else {

    return false;

}

}

`

• Search function query_full_array, change it to:
  `

function query_full_array($sql, $noerrmsg = false) {

if ($cache = get_cache($sql))

    return $cache;

$result = query($sql, $noerrmsg);

if ($result) {

    $allrows = array();

    while ($row = mysql_fetch_assoc($result))

        $allrows[] = $row;

    store_cache($sql, $allrows);

    return $allrows;

}

else {

    return false;

}

}

`

• Last thing, add two functions in functions-db.php. You could change “cachedirectory” to your cache directory, and change $cache_time_out to the expire time you want.
  `

function store_cache($query, $result_cache) {

$cache_time_out = 600;

if (preg_match("/^(insert|delete|update|replace)\s+/i",$query))

    return;

if (stristr($query, "ORDER BY RAND"))

    return;

$key = 'sql_' . md5($query);

$val = serialize($result_cache);

eaccelerator_put($key, $val, $cache_time_out);

}

function get_cache($query) {

if (preg_match("/^(insert|delete|update|replace)\s+/i",$query))

    return;

if (stristr($query, "ORDER BY RAND"))

    return;

$key = 'sql_' . md5($query);

$val = eaccelerator_get($key);

if ( $val != NULL )

    return unserialize($val);

}

`

Oops! Posted in the wrong forum.
@admin: Please relocate this thread to the Gen. discussions.

Not really a problem, I don't really look at the "categories" anyway since I read mostly via RSS..:-)