No, it shouldn't be. Although it could be. It seems like ZendMM actually works as a sub-OS memory releaser.
[url]http://www.samspublishing.com/articles/article.asp?p=486511&rl=1[/url] wrote: Zend Memory Manager
The solution to memory leaks during request bailout is the Zend Memory Management (ZendMM) layer. This portion of the engine acts in much the same way the operating system would normally act, allocating memory to calling applications. The difference is that it is low enough in the process space to be request-aware so that when one request dies, it can perform the same action the OS would perform when a process dies. That is, it implicitly frees all the memory owned by that request. Figure 3.1 shows ZendMM in relation to the OS and the PHP process.
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Figure 3.1 Zend Memory Manager replaces system calls for per-request allocations.
In addition to providing implicit memory cleanup, ZendMM also controls the perrequest memory usage according to the php.ini setting: memory_limit. If a script attempts to ask for more memory than is available to the system as a whole, or more than is remaining in its per-request limit, ZendMM will automatically issue an E_ERROR message and begin the bailout process. An added benefit of this is that the return value of most memory allocation calls doesn't need to be checked because failure results in an immediate longjmp() to the shutdown part of the engine.
Now, it looks in php.ini for the memory limit, so it could be reading the wrong php.ini. Try disabling it, and if it works, you need to talk to your host about it. It seems that ZendMM is helpful, and thus should be used.
