Just came across this excellent research work done on memmove by T Herselman.
Bearing in mind memory is constantly moved in any database. This excellent set of library would be very handy for those who work
at the deep end of postgresql.
In a nut shell, the library checks the hardware available ,32/64 Intel (i core with SSE features loadu/storeu)) AMD then uses different function depending on the size of memory block
that has to be moved. The article also claims that the library also checks for signed and unsigned memory block, I haven’t checked this.
Excellent research and could be well worth checking out. As it could improve the performance of postgresql engine.
Please check the article for all your questions.
http://www.codeproject.com/Articles/1110153/Apex-memmove-the-fastest-memcpy-memmove-on-x-x-EVE