Как загружать предметы без увеличения памяти?

Я сделал этот плагин, который получает данные из источника JSON и показывает их в пользовательском типе поста в WordPress. В ленте 1000 элементов, и при импорте элементов возникает ошибка памяти. Я не могу увеличить предел памяти. Как я могу импортировать предметы?

<?php
/**
* @package Hello_Dolly
* @version 1.6
*/
/*
Plugin Name: Hello Dolly
Plugin URI: https://wordpress.org/plugins/hello-dolly/
Description: This is not just a plugin, it symbolizes the hope and enthusiasm of an entire generation summed up in two words sung most famously by Louis Armstrong: Hello, Dolly. When activated you will randomly see a lyric from <cite>Hello, Dolly</cite> in the upper right of your admin screen on every page.
Author: Matt Mullenweg
Version: 1.6
Author URI: http://ma.tt/
*/

function get_json() {
$slices = json_decode(file_get_contents('http://pf.tradetracker.net/?aid=1&type=json&encoding=utf8&fid=251713&categoryType=2&additionalType=2&limit=1000',true));
create_posttype();
if ($slices) {
foreach ($slices->products as $slice) {
$ID = $slice->ID;
$name = $slice->name;
$currency = $slice->price->currency;
$amount = $slice->price->amount;
$URL = $slice->URL;
$images = $slice->images;
$description = $slice->description;
/*  $categories = $slice->categories; */
/*  $brand = $slice->properties->brand; */
$producttype = $slice->properties->producttype;
$deliveryCosts = $slice->properties->deliveryCosts;
$SKU = $slice->properties->SKU;
$brand_and_type = $slice->properties->brand_and_type;
$thumbnailURL = $slice->properties->thumbnailURL;
$deliveryTime = $slice->properties->deliveryTime;
$imageURLlarge = $slice->properties->imageURLlarge;
$categoryURL = $slice->properties->categoryURL;
$EAN = $slice->properties->EAN;
$variations = $slice->variations;
/* Test to see each of them is correct.
if ($brand)
echo $brand."<br>";
else
echo "Some error";
*/
$my_post = array(
'post_type' => 'products',
'post_title'    =>  $name,
'post_content'  => 'This is my content',
'post_status'   => 'publish',
'post_author'   => 1,
/* 'post_category' => array(8,39) */
);

// Insert the post into the database and return the new post ID
$post_id = wp_insert_post( $my_post, $wp_error );
}
}
}// Our custom post type function
function create_posttype() {

register_post_type( 'Products',
// CPT Options
array(
'labels' => array(
'name' => __( 'Products' ),
'singular_name' => __( 'Product' )
),
'public' => true,
'has_archive' => true,
'rewrite' => array('slug' => 'products'),
)
);
}
// Hooking up our function to theme setup
add_action( 'init', 'create_posttype' );
add_shortcode( 'display_data', 'get_json' );

?>

Ошибка:
Неустранимая ошибка: максимальное время выполнения 30 секунд превышено в C: \ xampp \ htdocs \ wordpress \ wp-includes \ wp-db.php в строке 1877