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The links on the left will always have the latest version of the program ready for downloading. Let your mouse hoover over a link, and you will see the amount of RAM you need in order to run it. The highest performance version requires 67 GB of RAM, and the lowest needs only 650 MB.
Explicit hash table: Stores 64-bit hash number plus entire cube position in RAM for explicit verification that the positions must match, therefore the stored solution must be correct for that position.
Implicit hash table: Stores 64-bit hash number without the actual position, and requires the search to also probe the stored PV before being able to determine if the hash table position matches the cube being searched. Less RAM and slower with more CPU activity when hitting multiple solutions.
On my machine, roughly every 90 minutes, there is a 64-bit hash found during the search that matches a position in the table but is not a solution. This is why it is very important to verify that the 64-bit hash key is also really associated with the position in question. I thought 64-bits of hash safety would last until the sun would burn out, but this apparently is one of those Birthday Problem type of phenomena.
http://lightningcloudcomputing.com/OO_4x4x4/Rubiks_Revenge_4x4x4_Program.shtml
The links on the left will always have the latest version of the program ready for downloading. Let your mouse hoover over a link, and you will see the amount of RAM you need in order to run it. The highest performance version requires 67 GB of RAM, and the lowest needs only 650 MB.
- 5-TFS + Centers @ 7-TFS explicit hash table = 67 GB
- 5-TFS + Centers @ 7-TFS implicit hash table = 20 GB
- 4-TFS + Centers @ 7-TFS explicit hash table = 28 GB
- 4-TFS + Centers @ 7-TFS implicit hash table = 7 GB
- 4-TFS + Centers @ 6-TFS implicit hash table = 2 GB
- 3-TFS + Centers @ 6-TFS explicit hash table = 650 MB
Explicit hash table: Stores 64-bit hash number plus entire cube position in RAM for explicit verification that the positions must match, therefore the stored solution must be correct for that position.
Implicit hash table: Stores 64-bit hash number without the actual position, and requires the search to also probe the stored PV before being able to determine if the hash table position matches the cube being searched. Less RAM and slower with more CPU activity when hitting multiple solutions.
On my machine, roughly every 90 minutes, there is a 64-bit hash found during the search that matches a position in the table but is not a solution. This is why it is very important to verify that the 64-bit hash key is also really associated with the position in question. I thought 64-bits of hash safety would last until the sun would burn out, but this apparently is one of those Birthday Problem type of phenomena.
http://lightningcloudcomputing.com/OO_4x4x4/Rubiks_Revenge_4x4x4_Program.shtml
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