"…premature optimization is the root of all evil".
— Donald Knuth

I agree with the fact that we must do our source code level optimizations when we have finshed the construction stage or it is almost complete. I was searching articles and papers about optimizing C source code to be applied on my programs and libraries. I’ve collected some of those optimizations. But you must not confuse algorithm optimization, source code optimization and compiler optimization, since the first one refers to algorithm design and the second one just refers to the algorithm implementation, and both are sharing just few common approaches to formal reductions.

Java synchronization is usually made through the synchronized keyword. Synchronized allow users to create a mutex around certain variable, class or method, where a mutex allows concurrent access to it. By concurrent access we should understand access from multiple threads. If an operation is atomic, there one and only one process or thread executing it. Then, mutex based operations are atomic.

Dear pyxser users, I’m pleased to announce that I’ve released pyxser-1.3r. The current ChangeLog for this release is as follows (Update: There was bug in the pyxser-1.3r release, it is patched and working in pyxser-1.3r-p1):

I’ve recently designed the IPC Messaging facility for caffeine. I’ve integrated the data packer module with the state machine module, plus the core IPC Messaging routines. The process itself is quite simple, you load a state machine, or build one on runtime, to process IPC messages, and you just define an IPC messaging service, which hold the proper information to allow your applications to work within those facilities. I’m thinking to use a similar approach to build networking support for caffeine. Since the IPC Messaging Facility is thinked to work on top of the Process Pool facility, you need to define statically the proper service structure on your applications, and instead of random IPC keys, you must use a static one for each Messaging service.

On the post from Eduardo Silva: "vmsplice() + SPLICE_F_GIFT flag ??", he’s asking about the problem of EINVAL errno value on calling vmsplice(2) system call on Linux systems.

does anybody know why the linux syscall vmsplice() doesn’t work with the SPLICE_F_GIFT flag ?, per manual page it should be supported but i get the following error: