Re: Notes about fixing regexes and UTF-8 (yet again)

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Fri, Feb 17, 2012 at 3:48 AM, Heikki Linnakangas
> <heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
>> Recompiling is expensive, but if you cache the results for the session, it
>> would probably be acceptable.

> What if you did this ONCE and wrote the results to a file someplace?

That's still a cache, you've just defaulted on your obligation to think
about what conditions require the cache to be flushed. (In the case at
hand, the trigger for a cache rebuild would probably need to be a glibc
package update, which we have no way of knowing about.)

Before going much further with this, we should probably do some timings
of 64K calls of iswupper and friends, just to see how bad a dumb
implementation will be.

regards, tom lane