Hi, While auditing nbtcompare.c, I noticed that int2, oid, and oid8 sortsupport functions use custom local fastcmp helpers that are functionally equivalent to the existing ssup_datum_int32_cmp (for int2) and ssup_datum_unsigned_cmp (for oid, oid8).
This prevents these types from hitting the radix sort fast path added in commit ef3c3cf6d02 [1], which dispatches based on the comparator function pointer. The original 2021-2022 thread that introduced the ssup_datum_*_cmp helpers (commit 6974924347c, Apr 2022) [2] covered int4, int8, timestamp, date, and the abbreviated-key types (text, uuid, macaddr, inet, bytea). int2 and oid weren't called out in that discussion, and oid8 didn't exist at the time, it was added in Jan 2026 [3] and inherited the custom fastcmp pattern from oid, about a month before radix sort landed. This patch fills those gaps. Switching to the existing helpers makes these types eligible for radix sort. Benchmark (10M-row single-key sort): Type Before After Speedup ---- ------ ----- ------- int2 2440 ms 1778 ms ~27% oid 2875 ms 2073 ms ~28% oid8 2837 ms 2042 ms ~28% int4 -- 1765 ms (baseline) int8 -- 2031 ms (baseline) The patch just replaces the comparator assignment and removes the now-unused local fastcmp functions. No behavioral change and the helpers produce identical results. int2 uses ssup_datum_int32_cmp because there is no int16-specific helper, every int16 fits losslessly in int32, and int32_cmp is more efficient than signed_cmp (4-byte radix passes instead of 8). Other custom fastcmp users in core (float4/float8, varlena types) cannot be trivially switched due to NaN handling or locale-dependent comparison, so they are left as-is. Tested with make check (245/245 pass) and make isolation/check (128/128 pass). [1] https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=ef3c3cf6d02 [2] https://www.postgresql.org/message-id/flat/CA%2BhUKGJ2-eaDqAum5bxhpMNhvuJmRDZxB_Tow0n-gse%2BHG0Yig%40mail.gmail.com [3] https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=b139bd3b6 Thanks, Baji Shaik
0001-Use-ssup_datum_-_cmp-for-int2-oid-and-oid8-sort-supp.patch
Description: Binary data
