On Tue, Dec 27, 2016 at 6:50 PM, Peter Eisentraut
<peter.eisentraut@2ndquadrant.com> wrote:
> I don't have much experience with the abbreviated key stuff. I have
> filled in what I think should work, but it needs detailed review.
Thanks.
It occurs to me that the comparison caching stuff added by commit
0e57b4d8b needs to be considered here, too. When we had to copy the
string to a temp buffer anyway, in order to add the terminating NUL
byte expected by strcoll(), there was an opportunity to do caching of
comparisons at little additional cost. However, since ICU offers an
interface that you're using that doesn't require any NUL byte, there
is a new trade-off to be considered -- swallow the cost of copying
into our own temp buffer solely for the benefit of comparison caching,
or don't do comparison caching. (Note that glibc had a similar
comparison caching optimization itself at one point, built right into
strcoll(), but it was subsequently disabled.)
--
Peter Geoghegan