Magento 1.9 – Removing All Related Products

It looks like a core bug/regression we saw in 1.7 where the block and collection cache weren't working effectively for the navigation menu (catalog/navigation/top.phtml).

You can test by removing it, or just temporarily capture the output into a file with an ob_start and serve it from a static file/memcache.

Also, the hardware you are using doesn't sound huge and looks under specified for the size of the store you have. There is probably an I/O bottleneck there too - SAN storage + congested network = poor performance.

--

As a crude solution, you can adjust the block class for the navigation (dump get_class($this)) in top.phtml to identify it.

This will allow site-wide caching, without the category level caching that the new version invoked. Its also worth removing the is_active class from the tree renderer if you do this to avoid random menu items appearing selected (and implement a JS alternative instead).

public function getCacheTags()
{
  return parent::getCacheTags();
}
public function getCacheLifetime()
{
  return null;
}
public function getCacheKey()
{
  return parent::getCacheKey();
}
public function getCacheKeyInfo()
{
  $shortCacheId = array(
    'CATALOG_NAVIGATION',
    Mage::app()->getStore()->getId(),
    Mage::getDesign()->getPackageName(),
    Mage::getDesign()->getTheme('template'),
    Mage::getSingleton('customer/session')->getCustomerGroupId(),
    'template' => $this->getTemplate(),
    'name' => $this->getNameInLayout(),
  );
  $cacheId = $shortCacheId;
  $shortCacheId = array_values($shortCacheId);
  $shortCacheId = implode('|', $shortCacheId);
  $shortCacheId = md5($shortCacheId);
  $cacheId['short_cache_id'] = $shortCacheId;
  return $cacheId;
}

You can find here an extension that let's you bulk upload (or manually insert) product relations (upsell, crossell, related, and with some simple code changes you can add custom relations if you have any).
This explains how to use it..

You can create a csv file with product skus or ids to be related and their position in the relation:

34,55:2,17:4
99:1,80:10

What is after : means the position of the product in the relation. You can perform 3 different actions:

• Relate all on one line to first product in line.
• Relate all products on one line
• Relate all products among themselves