一个共享的Magento开发环境需要多少内存？

Question

We're using a shared server (on RackSpace) for Magento development. Each developer has his own sandbox, but PHP's memory_limit = 512M and when I try to inspect some objects [with Mage::log($someBigArray)] , I get failures, and Apache logs this:

[Mon Jan 23 15:47:35 2012] [error] [client 208.247.73.130] PHP Fatal error:  Allowed memory size of 268435456 bytes exhausted (tried to allocate 228065281 bytes) in /home/msmith/projects/ref/app/Mage.php on line 761, referer: http://ref.msmith.mage.example.com/checkout/cart/

My boss wants to increase the memory so that we can do this kind of logging. Currently we only have three developers on the box, but we want to be able to increase up to 15. How much memory would be appropriate to set for memory_limit in php.ini to support that many developers on a shared server?

Answer 1

1. As much as you can, although 15 developers aren't that many if you consider the amount of traffic you'll be bringing to your store once you launch

2. All the memory in the world won't fix your Allowed memory size of 268435456 bytes exhausted error. These errors crop up when PHP encounters circular recursive links between objects and keeps spooling infinite string representations into memory. Magento has a lot of these circular references.

Answer 2

You aren't using 512MB yet - note the allowed memory size indicated in the error log. In addition to PHP.ini, Magento sets the memory limit in several places, at least in my distribution (a BitNami image on Linux).

In htdocs I have .htaccess with:

############################################
## adjust memory limit

#    php_value memory_limit 64M
    php_value memory_limit 256M
    php_value max_execution_time 18000

This affects much of the application. There are also a few places in the code with

    @set_time_limit(0);
    @ini_set('memory_limit', '256M');

You can grep for these.

If the large array you are wanting to dump to the log is a Varien_Object, you could try dumping it like this:

    Mage::log(
        "My object: " .
        print_r($object->debug(),true),
        null,
        'MyLogfile.log'
    );

The debug method stops infinite recursion, but this will only work for sub classes of Varien_Object. Fortunately, many of the objects in Magento are derived from Varien_Object.