Postgres has own implementation of qsort. It is used only for Solaris,
because in some cases Solaris implementation was terrible slow.
Now, New qsort is present in the Solaris from version 9 update 6 and I
performed some quick test and the speed is very similarly with pg
implementation see bellow. The Solaris qsort only does not have test for
preordered array.
Is it time to "remove" PG qsort and use libc version for solaris 9, 10...?
There some useful links:
solaris qsort implementation
http://cvs.opensolaris.org/source/xref/on/usr/src/common/util/qsort.c
discuss about qsort
http://momjian.postgresql.org/cgi-bin/pgtodo?qsort
Regards Zdenek
PS: Test program is located on
http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=4489885
There is test result:
mode 1 2 3 4 5 6 7 8
pg 3.440 54.259 42.251 40.967 38.214 29.730 21.668 39.142
pg2 39.492 53.598 44.697 40.546 38.027 29.572 21.598 38.756
solaris 41.207 41.957 41.873 41.616 35.895 29.502 26.906 39.492
Pg2 test is without sort array prechecking.