Mdtest; B.2. Mdtest - Dell PowerEdge EL Manual

Improving NFS Performance on HPC Clusters with Dell Fluid Cache for DAS

B.2. mdtest

can be downloaded from http://sourceforge.net/projects/mdtest/. Version 1.8.3 was used in

mdtest

these tests. It was compiled and installed on a NFS share that was accessible by compute nodes.
is launched with mpirun. For these tests, Intel MPI version 4.1.0 was used. One million files
mdtest
were created, stated and unlinked concurrently from multiple NFS clients on the NFS server. The
following table describes the
mpirun ARGUMENT
-np
-hostfile
-d
-i
-b
-z
-L
-I
-y
-u
-C
-R
-T
-r
As with the IOzone random access patterns, the following procedure was followed to minimize cache
effects during the metadata testing:
•
Unmount NFS share on clients.
•
Stop the NFS service and umount the XFS file system on the server.
•
Mount XFS file system on the server and start the NFS service.
•
Mount NFS Share on clients.
command-line arguments.
mdtest
DESCRIPTION
Number of processes
Tells mpirun where the hostfile is
The directory mdtest should run in
The number of iterations the test will run
Branching factor of directory structure
Depth of the directory structure
Files only at leaf level of tree
Number of files per directory tree
Sync the file after writing
unique working directory for each task
Create files and directories
Randomly stat files
Only stat files and directories
Remove files and directories left over from run
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