Greg Stark <gsst...@mit.edu> writes: > On some architectures like intel accessing unaligned ints is just > slow. On others (Alpha and PPC iirc?) it is an immediate bus error.
To a first approximation, Intel is the *only* popular architecture that doesn't bus-error on unaligned accesses. (And I'm sure their chip designers rue the day that their predecessors chose to allow that.) There are some systems where the kernel trap handler then proceeds to emulate the unaligned access for you, but that gives new meaning to the word "slow". You definitely don't want to be doing it in a patch that's alleged to give a performance improvement. Speaking of which, what about some performance numbers? Like Heikki, I'm quite suspicious of whether there is any real-world gain to be had from this approach. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers