Product specifications
Table Of Contents
- Table of Contents
- 1 Introduction
- 2 Feature Overview
- 3 Step-by-Step Cluster Setup and MPI Usage Checklists
- 4 InfiniPath Cluster Setup and Administration
- Introduction
- Installed Layout
- Memory Footprint
- BIOS Settings
- InfiniPath and OpenFabrics Driver Overview
- OpenFabrics Drivers and Services Configuration and Startup
- Other Configuration: Changing the MTU Size
- Managing the InfiniPath Driver
- More Information on Configuring and Loading Drivers
- Performance Settings and Management Tips
- Host Environment Setup for MPI
- Checking Cluster and Software Status
- 5 Using QLogic MPI
- Introduction
- Getting Started with MPI
- QLogic MPI Details
- Use Wrapper Scripts for Compiling and Linking
- Configuring MPI Programs for QLogic MPI
- To Use Another Compiler
- Process Allocation
- mpihosts File Details
- Using mpirun
- Console I/O in MPI Programs
- Environment for Node Programs
- Environment Variables
- Running Multiple Versions of InfiniPath or MPI
- Job Blocking in Case of Temporary InfiniBand Link Failures
- Performance Tuning
- MPD
- QLogic MPI and Hybrid MPI/OpenMP Applications
- Debugging MPI Programs
- QLogic MPI Limitations
- 6 Using Other MPIs
- A mpirun Options Summary
- B Benchmark Programs
- C Integration with a Batch Queuing System
- D Troubleshooting
- Using LEDs to Check the State of the Adapter
- BIOS Settings
- Kernel and Initialization Issues
- OpenFabrics and InfiniPath Issues
- Stop OpenSM Before Stopping/Restarting InfiniPath
- Manual Shutdown or Restart May Hang if NFS in Use
- Load and Configure IPoIB Before Loading SDP
- Set $IBPATH for OpenFabrics Scripts
- ifconfig Does Not Display Hardware Address Properly on RHEL4
- SDP Module Not Loading
- ibsrpdm Command Hangs when Two Host Channel Adapters are Installed but Only Unit 1 is Connected to the Switch
- Outdated ipath_ether Configuration Setup Generates Error
- System Administration Troubleshooting
- Performance Issues
- QLogic MPI Troubleshooting
- Mixed Releases of MPI RPMs
- Missing mpirun Executable
- Resolving Hostname with Multi-Homed Head Node
- Cross-Compilation Issues
- Compiler/Linker Mismatch
- Compiler Cannot Find Include, Module, or Library Files
- Problem with Shell Special Characters and Wrapper Scripts
- Run Time Errors with Different MPI Implementations
- Process Limitation with ssh
- Number of Processes Exceeds ulimit for Number of Open Files
- Using MPI.mod Files
- Extending MPI Modules
- Lock Enough Memory on Nodes When Using a Batch Queuing System
- Error Creating Shared Memory Object
- gdb Gets SIG32 Signal Under mpirun -debug with the PSM Receive Progress Thread Enabled
- General Error Messages
- Error Messages Generated by mpirun
- MPI Stats
- E Write Combining
- F Useful Programs and Files
- G Recommended Reading
- Glossary
- Index
5–Using QLogic MPI
QLogic MPI Details
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mpihosts File Details
As noted in “Create the mpihosts File” on page 5-3, an mpihosts file (also called
a machines file, nodefile, or hostsfile) has been created in your current working
directory. This file names the nodes on which the node programs may run.
The two supported formats for the mpihosts file are:
hostname1
hostname2
...
or
hostname1:process_count
hostname2:process_count
...
In the first format, if the -np count (number of processes to spawn in the mpirun
command) is greater than the number of lines in the machine file, the hostnames
will be repeated (in order) as many times as necessary for the requested number
of node programs.
In the second format, process_count can be different for each host, and is
normally the number of available processors on the node. When not specified, the
default value is one. The value of process_count determines how many node
programs will be started on that host before using the next entry in the mpihosts
file. When the full mpihosts file is processed, and there are additional processes
requested, processing starts again at the start of the file.
There are several alternative ways of specifying the mpihosts file:
As noted in “Compile and Run an Example C Program” on page 5-3, you
can use the command line option -m:
$mpirun -np n -m mpihosts [other options] program-name
In this case, if the named file cannot be opened, the MPI job fails.
When the -m option is omitted, mpirun checks the environment variable
MPIHOSTS for the name of the MPI hosts file. If this variable is defined and
the file it names cannot be opened, the MPI job fails.
NOTE:
To create an mpihosts file, use the ibhosts program. It will generate a
list of available nodes that are already connected to the switch.