August 2, 2010
Pi - Computation
Start : 6:19 PM (JST) May 4, 2010
Finish: 1:12 AM (JST) August 3, 2010
Pi - Verification
64 hours (primary)
66 hours (secondary)
The main computation took 90 days on Shigeru Kondo's desktop. Verification was done using two separate computers.
Due to the size of this computation, a tremendous amount of memory was needed:
- Roughly 22 TB* of disk was needed to perform the computation.
- Another 3.8 TB of disk was needed to store the compressed output of decimal and hexadecimal digits.
If the digits were stored in an uncompressed ascii text file, the combined size of the decimal and hexadecimal digits would be 8.32 TB.
*TB = 240 bytes
Software for Computation:
The program that was used for the main computation is y-cruncher v0.5.4.9138 Alpha.
See main page: y-cruncher - A Multi-Threaded Pi Program
y-cruncher is a powerful multi-threaded program/benchmark that is becoming an increasingly popular tool within the computer enthusiast community. It was also used for the current world record for most digits computed for several other famous constants. (These include: e, Square Root of 2, Golden Ratio, Euler-Mascheroni Constant, Natural Log of 2, Apery's Constant, and Catalan's Constant.)
There are several aspects of y-cruncher that set it apart from most other similar Pi-crunching programs:
Software for Verification:
The program that was used for the verification is y-cruncher BBP v1.0.119.
See main page: y-cruncher BBP
This program implements the digit-extraction algorithm for Pi using the BBP formulas. It's sole purpose was to verify the main computation.
Shigeru Kondo's computer had the following specifications:
The full article that contains many of the technical details are here.
You can contact Shigeru Kondo at firstname.lastname@example.org.