Difference between revisions of "Ready"

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The send of assignment ''a:=b'' will only begin once the receive from process 1 has been issued. With the statement ''a:=c'' the send, even though it is [[nonblocking]], will only start once a matching receive has been issued too.
 
The send of assignment ''a:=b'' will only begin once the receive from process 1 has been issued. With the statement ''a:=c'' the send, even though it is [[nonblocking]], will only start once a matching receive has been issued too.
  
''Since: Version 0.41b''
+
''Since: Version 0.5''
  
 
[[Category:Type Library]]
 
[[Category:Type Library]]
 
[[Category:Compound Types]]
 
[[Category:Compound Types]]
 
[[Category:Communication Mode Types]]
 
[[Category:Communication Mode Types]]

Revision as of 18:44, 13 January 2013

Syntax

ready[ ]

Semantics

The ready type will force P2P Send to start only if a matching receive has been posted by the target processor. When used in conjunction with the nonblocking type, communication start will wait until a matching receive is posted. This type acts as a form of handshaking and can improve performance in some uses.

Example

var a:Int::allocated[single[on[1]]];
var b:Int::allocated[single[on[2]]] :: ready[];
var c:Int::allocated[single[on[2]]] :: ready[] :: nonblocking[];
a:=b;
a:=c;

The send of assignment a:=b will only begin once the receive from process 1 has been issued. With the statement a:=c the send, even though it is nonblocking, will only start once a matching receive has been issued too.

Since: Version 0.5