Author tim.peters
Recipients eric.smith, jdemeyer, mark.dickinson, rhettinger, sir-sigurd, tim.peters
Date 2018-09-24.05:50:59
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <1537768259.36.0.956365154283.issue34751@psf.upfronthosting.co.za>
In-reply-to
Content
BTW, those tests were all done under a 64-bit build.  Some differences in a 32-bit build:

1. The test_tuple hash test started with 6 collisions.  With the change, it went down to 4.  Also changing to the FNV-1a 32-bit multiplier boosted it to 8.  The test passes in all those cases.

2. For 4-tuples taken from range(-50, 51) omitting -1 and -2:  massive number of collisions under the current code.  Died with MemoryError with the change - ran out of memory to build the Counter recording all the distinct hash codes.

Changing it to 3-tuples instead:  somewhere around 140 collisions with the change, and also changing to the FNV-1a 32-bit multiplier eliminated all collisions.

All of this was done under Win 10, using Visual Studio 2017.
History
Date User Action Args
2018-09-24 05:50:59tim.peterssetrecipients: + tim.peters, rhettinger, mark.dickinson, eric.smith, jdemeyer, sir-sigurd
2018-09-24 05:50:59tim.peterssetmessageid: <1537768259.36.0.956365154283.issue34751@psf.upfronthosting.co.za>
2018-09-24 05:50:59tim.peterslinkissue34751 messages
2018-09-24 05:50:59tim.peterscreate