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    <p>The main difference between the two instances is related to object lifetime. </p> <p><code>T1</code> has dynamic allocation, meaning its lifetime ends when <code>delete</code> is called, <code>T2</code> has automatic allocation, meaning its lifetime ends when execution leaves the allocation's enclosing block.</p> <p>Object lifetime should be the primary decision factor when choosing between dynamic or automatic variables. </p> <p>The second decision factor should be object size. Automatic objects are generally stored on a "stack", which has a limited size. In contrast, dynamically allocated objects can have much larger sizes.</p> <p>A distant third factor could be locality of reference, which might mean, in some scenarios, that the indirection (<code>-&gt;</code>) will impose a minute performance penalty. That's something only a profiler can tell.</p> <blockquote> <p>I design the methods of T1 and T2 accordingly, meaning that in T1 I pretty much have only void functions that will operate on the this object and inside T2 I will have methods that will access the actual members.</p> </blockquote> <p>That doesn't really make much sense. Both classes can have members and non-void functions.</p> <p>Do note that dynamic memory allocations impose a cost and also, usually, a lock must be aquired internally by the memory allocator. You can try different allocators (like <a href="http://goog-perftools.sourceforge.net/doc/tcmalloc.html" rel="nofollow">TCMalloc</a> and others) which offer some performance improvements in multithreaded scenarios.</p> <p>With dynamic storage there is also the real thread of memory leaks, forgetting to call <code>delete</code>. This can be alleviated by using smart pointers but they add their own performance penalties.</p> <p>Overall, the only real issue, in a multithreaded environment or not, is whether you actually need the (lifetime or size) properties offered by dynamic allocation and are willing to pay its performance cost.</p> <p>(A cost that you should measure before making the decision. Perfect is the enemy of good enough.)</p>
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    1. PODifferences in memory management with these 2 function calls?
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    1. COLocking the memory is only really required if the pointer value is shared across multiple threads, if the allocation, use and deletion all occur in a single thread, then there is no need to lock the memory.
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