In PHP, (unlike what I originally thought) there is an overhead of calling static methods vs simple functions.
On a very simple bench, the overhead is over 30% of th
It has been a while since I have done any PHP but this is probably similar to what you expect in other programming environments.
It is likely that the static method requires some construction of a SomeClass object behind the scenes each time that it is called, whereas the function can just be executed without any startup cost. Creating an object could be costly depending on a number of things: destruction of existing objects by a garbage collector/reference counter, memory pressure causing fragmentation, suboptimal memory allocation policies in the C runtime etc.
It would be interesting to compare the method performance of an existing object. To do this create an instance of SomeClass and then call an instance method repeatedly.