Cron job stops when another one is running

Question

I have two cron jobs in my site (I'm using Elysia Cron). They are set in my own module. One runs every minute and one every hour. Code below:

function mymodule_cronapi($op, $job = NULL) {
    $items['Import J Data'] = array(
        'description' => 'Import J Data',
        'rule' => '* * * * *',
        'callback' => 'mymodule_import_j_data_cron',
    );
    $items['Import Q Data'] = array(
        'description' => 'Import Q Data',
        'rule' => '0 * * * *',
        'callback' => 'mymodule_import_q_data_cron',
    );
    return $items;
}

function mymodule_import_j_data_cron($what) {   
    mymodule_j_save_f_data();
    mymodule_j_save_c_data();
}

function mymodule_import_q_data_cron($what) {
    mymodule_q_save_data();
}

In my server (centOS), i have the following line in my crontab (with correct MYKEY and url):

* * * * * root wget -O - -q -t 1 http://.../cron.php?cron_key=[MYKEY] >/dev/null 2>&1

When the second job runs (the one set to run every hour), the other one stops and I get the following error in my site log:

Attempting to re-run cron while it is already running.

The firs job runs for about 15-20 minute. After it ends, the other one starts again.

My question is, it's not possible to have both cron jobs running at the same time? Am I missing some settings in elysia cron?

Answer 1

It looks like ultimate cron can run parallel jobs.