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--- principles:law_of_leaky_abstractions [2013-10-08 11:09] – christian
+++ principles:law_of_leaky_abstractions [2013-10-08 12:21] – example 3 christian
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 (this example is taken from ((Joel Spolsky: //[[http://joelonsoftware.com/articles/LeakyAbstractions.html|The Law of Leaky Abstractions]]//)))
+==== Example 3: List of further examples ====
+  * The virtual address space is leaky. Paging leads to a loss of performance. And page faults show up for example while iterating over a two-dimensional array.
+  * Platform details are leaky. The Java Virtual Machine does a pretty good job abstracting from the underlying operating system. But at least  when it comes to accessing files based on file paths, the underlying file system structure leaks through. On Windows you have "C:\" whereas on Unixoid systems you have "/usr", "/etc" and stuff.
+  * SQL is leaky. Some queries have a considerably lower performance than others despite being semantically equivalent.
+  * Network file systems (SMB, NFS, etc) are leaky because they are remote. The connection may break down and the access is much slower than local file access.
+  * The finiteness of real-world machines leaks. Programming languages are said to be Turing complete. They theoretically are as powerful as a Turing machine. In fact they are not. Turing machines are conceptual automata with infinite memory. But in the real world memory is finite. There can be OutOfMemoryErrors: RAM and hard disks and any other kind of storage can and do get full.
 ===== Description Status =====
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 ===== Further Reading =====