Computer Composition Searches

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A computer can be a useful tool to search for compositions, yet even with today's fast processors exhausting many composition searches is too big a task. This page has been created to keep a record of searches people have successfully completed in popular methods. If you have completely exhausted a computer search for compositions, please add an entry to the table below, stating any constraints you applied to the search, when you first ran it, and any other information you think would be of interest.

Exhaustive Composition Searches

Method Search Constraints Results Time/
Computer/
Program
Date Run by Notes
Cambridge Surprise Major >=5000 changes
Tenors together
Round blocks
Bob = 14, Single = 1234
9,997 compositions
255,138 rotations
9 days
P90 PC
SMC

1:42:30
2.2GHz Athlon X2
SMC32

1:03:04
3.2GHz Phenom X4
SMC32

1:03:00
4GHz Core i7 930*
SMC32

0:44:28
4.36GHz Core i7 6700K
SMC32

0:28:15
2.1 (4.9)GHz i7 12700K
SMC32

1995




2005




2010





2010




2016




2022


Graham John



Mark Davies



Simon Humphrey



Graham John



Graham John



Mark Davies

 
See Cambridge - The Full Monty



















*Leaving 7 processor threads idle!



i7 12700 can scale up from 2.1 to 4.9GHz; it also has two types of core, one faster than the other. Run times currently vary between this and over 50 minutes, potentially because of mischeduling to slower cores or reduction in clock boost. To be investigated.

Cambridge Surprise Major >=5000 changes
Tenors together
Snap finishes
Bob = 14, Single = 1234
15,416 compositions 13 days
PC
SMC32
1998 Graham John See Cambridge - The Full Monty
Cambridge Surprise Major >=5000 changes
Tenors together
Round blocks
Bob = 14, Single = 1256
152,915 compositions
3,739,182 rotations
47 days
2.8GHz i7-860
SMC32
2010 Mark Davies
Bristol Surprise Maximus 5000-5100 changes
Tenors together
Round blocks
Bob = 14, Single = 1234
202,384,361 compositions 47 hours
PC
SMC32
1998 Mark Davies
Yorkshire Surprise Maximus 5000-5100 changes
Tenors together
Round blocks
Bob = 14, Single = 1234, Big Bob=18
202,927,179 compositions 5 days, 23 hours
PC
SMC32
1998 Mark Davies
Plain Bob Minor 720 changes
Bob = 14, Single = 1234
1,440,339,152 compositions 18:16:25
2.8GHz i7-860
SMC32
2010 Mark Davies

Composing Program Benchmark

The "Full Monty" search for compositions of Cambridge Surprise Major is a useful benchmark both for measuring the efficiency of composing programs and the computers they run on. As shown in the table above, the first time this was completed was in 1995 using SMC on a Pentium 90, taking 9 days. The current record for this search is twenty-eight minutes and fifteen seconds run by Mark Davies using SMC32 on a Core i7 12700K processor at up to 4.9GHz in 2022. It is now over 20 years since SMC32 was written and as it is a 32-bit single-threaded application, it should be possible to significantly improve on this today by writing a multi-threaded 64-bit search engine for a modern top of the range processor. If you beat it, please update this page.