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* Replace random(), pg_erand48(), etc with a better PRNG API and algorithm.Tom Lane2021-11-281-25/+0
| | | | | | | | | | | | | | | | | | | Standardize on xoroshiro128** as our basic PRNG algorithm, eliminating a bunch of platform dependencies as well as fundamentally-obsolete PRNG code. In addition, this API replacement will ease replacing the algorithm again in future, should that become necessary. xoroshiro128** is a few percent slower than the drand48 family, but it can produce full-width 64-bit random values not only 48-bit, and it should be much more trustworthy. It's likely to be noticeably faster than the platform's random(), depending on which platform you are thinking about; and we can have non-global state vectors easily, unlike with random(). It is not cryptographically strong, but neither are the functions it replaces. Fabien Coelho, reviewed by Dean Rasheed, Aleksander Alekseev, and myself Discussion: https://postgr.es/m/alpine.DEB.2.22.394.2105241211230.165418@pseudo
* Update copyright for 2021Bruce Momjian2021-01-021-1/+1
| | | | Backpatch-through: 9.5
* Update copyrights for 2020Bruce Momjian2020-01-011-1/+1
| | | | Backpatch-through: update all files in master, backpatch legal files through 9.4
* Update copyright for 2019Bruce Momjian2019-01-021-1/+1
| | | | Backpatch-through: certain files through 9.4
* Update copyright for 2018Bruce Momjian2018-01-021-1/+1
| | | | Backpatch-through: certain files through 9.3
* Update copyright via script for 2017Bruce Momjian2017-01-031-1/+1
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* Update copyright for 2016Bruce Momjian2016-01-021-1/+1
| | | | Backpatch certain files through 9.1
* Update copyright for 2015Bruce Momjian2015-01-061-1/+1
| | | | Backpatch certain files through 9.0
* Update copyright for 2014Bruce Momjian2014-01-071-1/+1
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Update copyrights for 2013Bruce Momjian2013-01-011-1/+1
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Update copyright notices for year 2012.Bruce Momjian2012-01-011-1/+1
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* Make pgbench use erand48() rather than random().Robert Haas2011-08-031-1/+1
| | | | | | | | | | | | | | | | | | glibc renders random() thread-safe by wrapping a futex lock around it; testing reveals that this limits the performance of pgbench on machines with many CPU cores. Rather than switching to random_r(), which is only available on GNU systems and crashes unless you use undocumented alchemy to initialize the random state properly, switch to our built-in implementation of erand48(), which is both thread-safe and concurrent. Since the list of reasons not to use the operating system's erand48() is getting rather long, rename ours to pg_erand48() (and similarly for our implementations of lrand48() and srand48()) and just always use those. We were already doing this on Cygwin anyway, and the glibc implementation is not quite thread-safe, so pgbench wouldn't be able to use that either. Per discussion with Tom Lane.
* Stamp copyrights for year 2011.Bruce Momjian2011-01-011-1/+1
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* Remove cvs keywords from all files.Magnus Hagander2010-09-201-1/+1
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* Update copyright for the year 2010.Bruce Momjian2010-01-021-2/+2
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* Update copyright for 2009.Bruce Momjian2009-01-011-2/+2
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* Update copyrights in source tree to 2008.Bruce Momjian2008-01-011-2/+2
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* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-051-2/+2
| | | | back-stamped for this.
* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-051-2/+2
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* Fix a whole bunch of #includes that were either wrong or redundant.Tom Lane2005-07-281-3/+2
| | | | | | | | The first rule of portability for us is 'thou shalt have no other gods before c.h', and a whole lot of these files were either not including c.h at all, or including random system headers beforehand, either of which sins can mess up largefile support nicely. Once you have included c.h, there is no need to re-include what it includes, either.
* Tag appropriate files for rc3PostgreSQL Daemon2004-12-311-2/+2
| | | | | | | | Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
* Update copyright to 2004.Bruce Momjian2004-08-291-2/+2
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* $Header: -> $PostgreSQL Changes ...PostgreSQL Daemon2003-11-291-1/+1
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* Update /port C header descriptions.Bruce Momjian2003-11-111-1/+14
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* Move libc replacement files from src/backend/port to src/port.Bruce Momjian2002-07-181-0/+13