Message receiving system for use in parallel computer system

A message receiving method in a parallel computer system having a plurality of computers, each computer comprising a message buffer for temporarily storing a message received from a first computer over a network and a message handler for receiving a request, from a processor provided in a second computer to which the message buffer belongs, to receive the message to be transmitted from the first computer and temporarily stored in the message buffer, comparing a message type included in the request to receive a message with a message type included in a header of an arrived message, and determining whether or not the arrived message is a message requested from the processor, said buffer comprising the steps of:

• determining by the message handler whether or not a requested message has been received from the network on receipt of a receive-a-message request from the processor;
• and
• starting by said message handler transmitting the requested message from said message buffer to the user area in the memory of the second computer if the requested message is received before reception of the receive-a-message request, and the message has been completely transmitted to said message buffer;
• returning a signal to the processor in response to the receive-a-message request immediately after said starting transferring the message;
• and
• preventing the processor from accessing a portion of the user area to which the message has not been transferred yet to realize overlap between reception of a message and execution by a processor.

A message receiving method in a parallel computer system having a plurality of computers, each computer comprising a message buffer for temporarily storing a message received from a first computer over a network and a message handler for receiving a request, from a processor provided in a second computer to which the message buffer belongs, to receive the message to be transmitted from the first computer and temporarily stored in the message buffer, comparing a message type included in the request to receive a message with a message type included in a header of an arrived message, and determining whether or not the arrived message is a message requested from the processor, said method comprising the steps of:

• determining by the message handler whether or not a requested message has been received from the network on receipt of a receive-a-message request from the processor;
• and
• starting by said message handler transmitting the requested message from said message buffer to the user area in the memory of the second computer if a header of the requested message is received before reception of the receive-a-message request, and the message is being transmitted to said message buffer;
• returning a signal to the processor in response to the receive-a-message request immediately after said starting transferring the message;
• and
• preventing the processor from accessing a portion of the user area to which the message has not been transferred yet to realize overlap between reception of a message and execution by a processor.

A message receiving method in a parallel computer system having a plurality of computers, each computer comprising a message buffer for temporarily storing a message received from a first computer over a network and a message handler for receiving a request, from a processor provided in a second computer to which the message buffer belongs, to receive the message to be transmitted from the first computer and temporarily stored in the message buffer, and comparing a message type included in the request to receive a message with a message type included in a header of an arrived message, and determining whether or not the arrived message is a message requested from the processor, said method comprising the steps of:

• invalidating by the processor a message receiving area in the cache memory before issuing a receive-a-message request to the message handler;
• returning a signal to the processor by the message handler in response to said receive-a-message request after starting transferring the message received over the network to the cache memory;
• and
• preventing the processor from accessing a portion in the cache memory to which the message has not been transferred yet.

A message receiving method in a parallel computer system having a plurality of computers, each computer comprising a message buffer for temporarily storing a message received from a first computer over a network and a message handler for receiving a request, from a processor provided in a second computer to which the message buffer belongs, to receive the message to be transmitted from the first computer and temporarily stored in the message buffer, and comparing a message type included in the request to receive a message with a message type included in a header of an arrived message, and determining whether or not the arrived message is a message requested from the processor, said method comprising the steps of:

• determining by the message handler whether or not a requested message has been received through the network on receipt of a receive-a-message request from the processor;
• starting by the processor another process to cover delay in a process up to receipt of the message if said receive-a-message request is received before actual receipt of the message;
• and
• directly transferring by the message handler the message to the user area when the message actually has been received, and preventing the processor from accessing the user area in which the message is to be stored in a memory of the second computer.