Method for performing alltoall communication in parallel computers
AssigneeHitachi, Ltd.
InventorKimihide Kureya
Life of this patent
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Abstract
The present invention reduces the processing time required for alltoall communications in a parallel computer. When performing alltoall communications in a parallel computer, the number of transfer data units and the number of computers are used as parameters to select between a method where a temporary work buffer is allocated in the memory of each computer and non-contiguous data is exchanged between computers and a method where data is exchanged between computers without allocating temporary work buffers.
Claims5
A method of performing parallel communication for a parallel computer system comprising n computers (n being a positive integer) which are respectively assigned unique identifying numbers and including means for communicating sending and receiving non-contiguous data formed from m fixed-length blocks (m being a positive integer) stored in a storage means of said computers, the method comprising the steps of:
- if the number of said computers is not a power of 2, allocating for each of said computers in said storage means first and second areas, each area being capable of storing M data blocks, M being the smallest power of 2 larger than said non-contiguous block count m;
- forming an N×M block region from N-n second areas and said first area, where N is the smallest power of 2 larger than said number of computers n;
- and using said the N×M block area to send and receive non-contiguous data.
Dependencies are inferred from the claim text.