From: hjstein@bfr.co.il (Harvey J. Stein) Newsgroups: comp.parallel.pvm,comp.parallel.mpi Subject: Re: Is there a synchronous send routine in PVM? Date: 14 Sep 1998 15:00:09 +0200 Organization: Unspecified Organization Message-Id: References: <35F670E7.EC0E960E@pvmcube4.snu.ac.kr> <35F8BFDA.417EEB1F@iinet.com.au> Cc: hjstein@bfr.co.il Xref: ukc comp.parallel.pvm:7600 comp.parallel.mpi:4035 Colin Scott writes: > Bo-sung Lee wrote: > > > > I know pvm_send and pvm_psend are asynchronous. Asynchronous send > > routine is useful in overlapping communication with compution. But > > because of some special need, I want to use synchoronouse send routine > > in PVM. > > > > In MPI, mpi_ssend routine is exist. But there is no one in PVM. So if > > someone has good idea or experience about synchoronous send routine in > > PVM, comment it. > > Tou could try using the pvm_barrier call. Send the messages, and use > pvm_barrier to cause all the tasks to start processing at the same time. > According to the PVM book (Geist et al) "the logical function of the > pvm_barrier call is to provide a group synchronisation". I don't know > how closely together all the tasks will return from pvm_barrier though. It'll be hard to use pvm_barrier to get the effect of a syncronous send because of the group nature. You'd be able to get close to the behavior of mpi_ssend by having the sender send a message & wait for an acknowledgement & having the receiver send back an acknowledgement when the message is received. -- Harvey J. Stein BFM Financial Research hjstein@bfr.co.il