CFD Online Logo CFD Online URL
Home > Forums > Main CFD Forum

MPI buffer size for Send/Recv

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   April 14, 2005, 08:36
Default MPI buffer size for Send/Recv
Posts: n/a
I am using Scali MPI in my code. I use the MPI_Send() and MPI_Recv() routines for sending information between the nodes. I increase the amount of data that is sent between nodes and everything works fine, until a certain amount of data when the communications just become idle and the program gets stucked, as if the different processors do not receive the information they are waiting for and just keep on waiting for ever.

I have read something about the size of the buffer that is assign for MPI communiations. Could that be the problem? That I am sending more information than the maximum buffer size?

In this case, if I change to the nonblocking routines MPI_Isend() and MPI_Irecv(), do I solve the problem? Or is there any way of increasing the available buffer size?

Thanks in adavance.

  Reply With Quote

Old   April 15, 2005, 10:03
Default Re: MPI buffer size for Send/Recv
Posts: n/a
I had a similar problem with my code. The fix for me was to use Isend and Irecv. Make sure you use a MPI_Waitall at an appropriate place to insure all the messages are complete.
  Reply With Quote

Old   April 15, 2005, 11:21
Default Re: MPI buffer size for Send/Recv
Posts: n/a
Thanks very much! I will try that.
  Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Superlinear speedup in OpenFOAM 13 msrinath80 OpenFOAM Running, Solving & CFD 18 March 3, 2015 06:36
critical error during installation of openfoam Fabio88 OpenFOAM Installation 21 June 2, 2010 03:01
OF 1.6 | Ubuntu 9.10 (64bit) | GLIBCXX_3.4.11 not found piprus OpenFOAM Installation 22 February 25, 2010 14:43
Phase locked average in run time panara OpenFOAM 2 February 20, 2008 15:37
fluent add additional zones for the mesh file SSL FLUENT 2 January 26, 2008 12:55

All times are GMT -4. The time now is 05:50.