Commit Graph

3 Commits

Author SHA1 Message Date
Tom Lane da256a4a7f Pre-beta mechanical code beautification.
Run pgindent, pgperltidy, and reformat-dat-files.

The pgindent part of this is pretty small, consisting mainly of
fixing up self-inflicted formatting damage from patches that
hadn't bothered to add their new typedefs to typedefs.list.
In order to keep it from making anything worse, I manually added
a dozen or so typedefs that appeared in the existing typedefs.list
but not in the buildfarm's list.  Perhaps we should formalize that,
or better find a way to get those typedefs into the automatic list.

pgperltidy is as opinionated as always, and reformat-dat-files too.
2024-05-14 16:34:50 -04:00
Nathan Bossart 41c51f0c68 Optimize visibilitymap_count() with AVX-512 instructions.
Commit 792752af4e added infrastructure for using AVX-512 intrinsic
functions, and this commit uses that infrastructure to optimize
visibilitymap_count().  Specificially, a new pg_popcount_masked()
function is introduced that applies a bitmask to every byte in the
buffer prior to calculating the population count, which is used to
filter out the all-visible or all-frozen bits as needed.  Platforms
without AVX-512 support should also see a nice speedup due to the
reduced number of calls to a function pointer.

Co-authored-by: Ants Aasma
Discussion: https://postgr.es/m/BL1PR11MB5304097DF7EA81D04C33F3D1DCA6A%40BL1PR11MB5304.namprd11.prod.outlook.com
2024-04-06 22:58:23 -05:00
Nathan Bossart 792752af4e Optimize pg_popcount() with AVX-512 instructions.
Presently, pg_popcount() processes data in 32-bit or 64-bit chunks
when possible.  Newer hardware that supports AVX-512 instructions
can use 512-bit chunks, which provides a nice speedup, especially
for larger buffers.  This commit introduces the infrastructure
required to detect compiler and CPU support for the required
AVX-512 intrinsic functions, and it adds a new pg_popcount()
implementation that uses these functions.  If CPU support for this
optimized implementation is detected at runtime, a function pointer
is updated so that it is used by subsequent calls to pg_popcount().

Most of the existing in-tree calls to pg_popcount() should benefit
from these instructions, and calls with smaller buffers should at
least not regress compared to v16.  The new infrastructure
introduced by this commit can also be used to optimize
visibilitymap_count(), but that is left for a follow-up commit.

Co-authored-by: Paul Amonson, Ants Aasma
Reviewed-by: Matthias van de Meent, Tom Lane, Noah Misch, Akash Shankaran, Alvaro Herrera, Andres Freund, David Rowley
Discussion: https://postgr.es/m/BL1PR11MB5304097DF7EA81D04C33F3D1DCA6A%40BL1PR11MB5304.namprd11.prod.outlook.com
2024-04-06 21:56:23 -05:00