Message 233073 - Python tracker

➜

This issue tracker has been migrated to GitHub, and is currently read-only.
For more information, see the GitHub FAQs in the Python's Developer Guide.

Author	rhettinger
Recipients	rhettinger
Date	2014-12-24.05:52:11
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1419400332.58.0.470390691587.issue23107@psf.upfronthosting.co.za>
In-reply-to

Content
The lookkey functions currently check for an exact key match in the inner search-loop. Move that test to occur after a matching hash is found rather than testing every entry. This gives a modest speed improvement. --- n = 10,000 --- $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 1000 loops, best of 3: 396 usec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 1000 loops, best of 3: 367 usec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 1000 loops, best of 3: 375 usec per loop $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 1000 loops, best of 3: 389 usec per loop $ $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 1000 loops, best of 3: 656 usec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 1000 loops, best of 3: 657 usec per loop $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 1000 loops, best of 3: 662 usec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 1000 loops, best of 3: 642 usec per loop -- n = 1,000,000 -- $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 10 loops, best of 3: 67 msec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 10 loops, best of 3: 48.2 msec per loop $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 10 loops, best of 3: 59.9 msec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t' 10 loops, best of 3: 49.1 msec per loop $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 10 loops, best of 3: 173 msec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 10 loops, best of 3: 152 msec per loop $ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 10 loops, best of 3: 170 msec per loop $ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u' 10 loops, best of 3: 167 msec per loop

The lookkey functions currently check for an exact key match in the inner search-loop.  Move that test to occur after a matching hash is found rather than testing every entry.  This gives a modest speed improvement.

--- n = 10,000 ---
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
1000 loops, best of 3: 396 usec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
1000 loops, best of 3: 367 usec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
1000 loops, best of 3: 375 usec per loop
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
1000 loops, best of 3: 389 usec per loop
$ 
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
1000 loops, best of 3: 656 usec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
1000 loops, best of 3: 657 usec per loop
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
1000 loops, best of 3: 662 usec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
1000 loops, best of 3: 642 usec per loop

-- n = 1,000,000 --
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
10 loops, best of 3: 67 msec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
10 loops, best of 3: 48.2 msec per loop
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
10 loops, best of 3: 59.9 msec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&t'
10 loops, best of 3: 49.1 msec per loop
 
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
10 loops, best of 3: 173 msec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
10 loops, best of 3: 152 msec per loop
$ ~/baseline/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
10 loops, best of 3: 170 msec per loop
$ ~/tight/python.exe -m timeit -s 'from time_tight import s,t,u' 's&u'
10 loops, best of 3: 167 msec per loop

History
Date	User	Action	Args
2014-12-24 05:52:12	rhettinger	set	recipients: + rhettinger
2014-12-24 05:52:12	rhettinger	set	messageid: <1419400332.58.0.470390691587.issue23107@psf.upfronthosting.co.za>
2014-12-24 05:52:12	rhettinger	link	issue23107 messages
2014-12-24 05:52:11	rhettinger	create