On 21 June 2012 01:22, Peter Geoghegan <peter@2ndquadrant.com> wrote:
> I've written a very small C++ program, which I've attached, that
> basically proves that this can still make a fairly large difference -
> I hope it's okay that that it's C++, but that allowed me to write the
> program quickly, with no dependencies for anyone who cares to try this
> out, other than a C++ compiler and the standard library.
So, it turns out that with a relatively expensive to sort collation
like hu_HU.UTF-8, the difference here is huge:
[peter@peterlaptop strxfrm_test]$ ./a.out
locale set: hu_HU.UTF-8
Time elapsed with strcoll: 11.122695 seconds
Time elapsed with strxfrm optimization: 2.328365 seconds
Time elapsed with strcoll: 11.404160 seconds
Time elapsed with strxfrm optimization: 2.355684 seconds
Time elapsed with strcoll: 11.411680 seconds
Time elapsed with strxfrm optimization: 2.342553 seconds
Time elapsed with strcoll: 11.415693 seconds
Time elapsed with strxfrm optimization: 2.343593 seconds
Time elapsed with strcoll: 11.428686 seconds
Time elapsed with strxfrm optimization: 2.345204 seconds
*****strcoll average: 11.356583 strxfrm average: 2.343080*****
--
Peter Geoghegan http://www.2ndQuadrant.com/
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