used shared memory on a node to share EOS table

Comments (6)

1. 

   Roland Haas reporter

   • changed status to open
   • removed comment

   • 2012-07-31T11:36:15+00:00
2. 

   Erik Schnetter

   • removed comment

   doBcast is not defined reliably; it relies on a process id, which may be the same on different nodes. Using MPI_Hostname may be a better way. Carpet already collects host names and converts them to integers; you may be able to query this.

   I don't think it is legal to use different sizes on different processes in MPI_Bcase. I would assume that the sender still sends all data, but the receiver ignores some of it, and the data remain stuck in a buffer. MPI_Alltoallv may be necessary.

   I still worry that the shared memory segments are created in the code, but are never deleted. If I recall correctly, the operating system does not delete them automatically when a process ends. The command "icps" lists all such segments -- please check whether you have a memory leak.

   • 2012-08-09T15:39:13+00:00
3. 

   Erik Schnetter

   • changed status to open
   • assigned issue to
   • removed comment

   • 2012-09-15T17:41:23+00:00
4. 

   Roland Haas reporter

   • removed comment

   All of Erik's comments are correct, the current patch is broken and full of bugs. Getting this right is a bit of a hassle due to the rather odd semantics of SYSV IPC constructs and the desire to have a clean implementation. Not terribly high priority to anyone as far as I know so don't expect this to happen soon.

   • 2012-09-15T18:02:25+00:00
5. 

   Roland Haas reporter

   • changed status to resolved
   • removed comment

   The benefit of this seems small right now and it greatly adds to the complexity of the code. Shelfed for now. Re-open with cleaner code if required.

   • 2013-12-02T11:48:51+00:00
6. 

   Roland Haas reporter

   • edited description
   • changed status to closed

   • 2019-02-21T19:53:42+00:00
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