Belvg_SmartyApplyCatalogRule_Model_Rule

 class Belvg_SmartyApplyCatalogRule_Model_Rule extends Mage_CatalogRule_Model_Rule  {
 
	public function applyRule($rule_id)
    {
    	$rule = Mage::getModel('catalogrule/rule')->load($rule_id);
        $this->_getResource()->updateRuleProductData($rule); //solution of the problem
        $this->_getResource()->applyAllRulesForDateRange();
        $this->_invalidateCache();
        $indexProcess = Mage::getSingleton('index/indexer')->getProcessByCode('catalog_product_price');
        if ($indexProcess) {
            $indexProcess->reindexAll();
        }
    }
 
}

catalog-price-rule-optimization

<?php
 /**
     * Apply all active catalog price rules
     */
public function applyRulesAction()
    {
        $errorMessage = Mage::helper('catalogrule')->__('Unable to apply rules.');
        try {
            Mage::getModel('catalogrule/rule')->applyAll(); //the major culprit
            Mage::getModel('catalogrule/flag')->loadSelf()
                ->setState(0)
                ->save();
            $this->_getSession()->addSuccess(Mage::helper('catalogrule')->__('The rules have been applied.'));
        } catch (Mage_Core_Exception $e) {
            $this->_getSession()->addError($errorMessage . ' ' . $e->getMessage());
        } catch (Exception $e) {
            $this->_getSession()->addError($errorMessage);
        }
        $this->_redirect('*/*');
    }
 
    /**
     * Apply all price rules, invalidate related cache and refresh price index
     *
     * @return Mage_CatalogRule_Model_Rule
     */
    public function applyAll()
    {
        $this->getResourceCollection()->walk(array($this->_getResource(), 'updateRuleProductData')); //the function 'updateRuleProductData' is applied by turn to each rule 
        $this->_getResource()->applyAllRulesForDateRange();
        $this->_invalidateCache();
        $indexProcess = Mage::getSingleton('index/indexer')->getProcessByCode('catalog_product_price');
        if ($indexProcess) {
            $indexProcess->reindexAll();
        }
    }