EFFICIENT CPU MAILBOX READ ACCESS TO GPU MEMORY

Techniques are disclosed for peer-to-peer data transfers where a source device receives a request to read data words from a target device. The source device creates a first and second read command for reading a first portion and a second portion of a plurality of data words from the target device, respectively. The source device transmits the first read command to the target device, and, before a first read operation associated with the first read command is complete, transmits the second read command to the target device. The first and second portions of the plurality of data words are stored in a first and second portion a buffer memory, respectively. Advantageously, an arbitrary number of multiple read operations may be in progress at a given time without using multiple peer-to-peer memory buffers. Performance for large data block transfers is improved without consuming peer-to-peer memory buffers needed by other peer GPUs.