Re: [PATCH] backend: compare word-at-a-time in bcTruelen

Hi all,

> Speaking of which, what about some performance numbers?

OK, benchmarks done:
http://ozlabs.org/~jk/projects/db/data/postgres.bcTruelen/

Summary: small increase in performance (~1-2% on my machine), at about 
1.5 standard deviations from the mean. Profiles show a decent drop in 
hits within bcTruelen.

However: Sysbench seems to be quite heavy with the fixed-width char 
types, so may end up calling bcTruelen more than most workloads. Would 
be nice to get some x86 numbers too, but I don't have a suitable machine 
here.

So: The increase in performance is positive on this workload, albeit 
fairly minor. Downside is increased code complexity.

Will re-send the patch once I work out how to get git to create a 
context diff...

Cheers,


Jeremy