mdtest(1)

💖 NAME 💖

okay bestie, this is mdtest(1), the manual page for mdtest — test file system metadata performance. That's literally the whole name vibe: it tests file system metadata performance. 💅

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🌸 SYNOPSIS 🌸

mdtest [-options]

✨ DESCRIPTION ✨

okay so mdtest is a file system metadata performance test designed to run in a cluster MPI environment against parallel file systems. no cap.

In each iteration of the test, each MPI task creates, stats, and removes the specified number of directories and/or files and measures the performance in ops/second. After all the iterations complete, the maximum, minimum, mean ops/sec and the std. deviation are reported for each operation. periodt. 💖

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🎀 OPTIONS 🎀

• -b branching_factor — The branching factor of the hierarchical directory structure. Default: 1.
• -B — No barriers will be taken between the phases (create/stat/remove) of the tests.
• -c — Use collective creates, meaning task 0 does all the creates.
• -C — Only perform the create phase of the tests.
• -d testdir[@testdir2] — The directory in which the tests will run. For multiple paths, must use fully-qualified pathnames. Default: working directory of mdtest.
• -D — Perform test on directories only (no files).
• -e bytes — Set the number of Bytes to read from each file. Default: 0.
• -E — Only perform the read phase of the tests.
• -f first — The first number of tasks on which the test will run. Default: 0.
• -F — Perform test on files only (no directories).
• -g — Use global default directory layout for test subdirectories (deletes inherited striping layout - Lustre only).
• -h — Display help message.
• -i iterations — The number of iterations the test will run. Default: 1.
• -I items_per_directory — The number of items per directory in the tree. Default: 0.
• -l last — The last number of tasks on which the test will run. Default: 0.
• -L — Files/directories only created at the leaf level of the tree.
• -n number_of_items — Every process will creat/stat/remove # directories and files. Default: 0.
• -N stride — Stride # between neighbor tasks for file/dir stat, 0 = local. Default: 0.
• -p seconds — Pre-iteration delay (in seconds).
• -P — Print both the file creation rate and the elapsed time.
• -r — Only perform the remove phase of the tests.
• -R[seed] — Randomly stat files. There is an optional argument that provides a seed to the random number generator. Note: There is no space between the -R and the seed if one is provided.
• -s stride — Stride between the number of tasks for each test. Default: 1.
• -S — Shared file access (file only, no directories).
• -t — Include unique working directory management overhead in the results (presumes -u option).
• -T — Only perform the stat phase of the tests.
• -u — Create a unique working directory for each task (presumes -d option).
• -v — Increase verbosity (each instance of option increments by one).
• -V value — Set verbosity value. Default: 0.
• -w bytes — Set the number of Bytes to write to each file after it is created. Default: 0.
• -W seconds — Specify the stonewall time in seconds. When the stonewall timer has elapsed, the rank with the highest number of creates sets number_of_items for the other ranks, so that all ranks create the same number of files.
• -x filename — Filename to use for stonewall synchronization between processes.
• Y — Call the sync command after each phase, which is included in the timing. Note that it causes all IO to be flushed from the nodes. (yes, it's just Y, no dash — that's how it's listed here 💅)
• -z tree_depth — The depth of the hierarchical directory tree. Default: 0.

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🦋 EXAMPLES 🦋

Example 1

okay so Example 1 is literally this:

$ mpirun -n 2 ./mdtest -d /tmp/z -n 100 -i 2

-- started at 11/23/2009 09:05:29 --

mdtest-1.8.1 was launched with 2 total task(s) on 1 nodes
Command line used: ./mdtest -d /tmp/z -n 100 -i 2
Path: /tmp
FS: 28.8 GiB   Used FS: 8.6%   8.6%Inodes: 1.8 Mi   Used Inodes: 5.1%

time to create tree: 0.000078 sec
tree creation rate: 12826.617737 ops/sec

2 tasks, 200 files/directories

SUMMARY: (of 2 iterations)
   Operation                  Max        Min       Mean    Std Dev
   ---------                  ---        ---       ----    -------
   Directory creation:  21489.415  17447.551  19468.483   2020.932
   Directory stat    : 154657.227  28731.061  91694.144  62963.083
   Directory removal : 146756.613  21489.415  84123.014  62633.599
   File creation     :  42024.989  28731.061  35378.025   6646.964
   File stat         : 146756.613  17447.551  82102.082  64654.531
   File removal      : 156884.384  42024.989  99454.686  57429.698

time to remove tree: 0.001031 sec
tree removal rate: 970.005550 ops/sec

-- finished at 11/23/2009 09:05:29 --

Example 2

and Example 2 is giving this energy:

$ mpirun -np 2 -H pc6 ./mdtest -d /tmp/z -b 2 -z 3 -I 10

-- started at 11/23/2009 09:09:23 --

mdtest-1.8.1 was launched with 2 total task(s) on 1 nodes
Command line used: ./mdtest -d /tmp/z -b 2 -z 3 -I 10
Path: /tmp
FS: 28.8 GiB   Used FS: 8.6%   8.6%Inodes: 1.8 Mi   Used Inodes: 5.1%

time to create tree: 0.000765 sec
tree creation rate: 19605.659084 ops/sec

2 tasks, 300 files/directories

SUMMARY: (of 1 iterations)
   Operation                  Max        Min       Mean    Std Dev
   ---------                  ---        ---       ----    -------
   Directory creation:  29365.707  29365.707  29365.707      0.000
   Directory stat    : 123701.455 123701.455 123701.455      0.000
   Directory removal :  25623.459  25623.459  25623.459      0.000
   File creation     :  38704.743  38704.743  38704.743      0.000
   File stat         : 125477.782 125477.782 125477.782      0.000
   File removal      :  51911.845  51911.845  51911.845      0.000

time to remove tree: 0.000940 sec
tree removal rate: 15960.060883 ops/sec

-- finished at 11/23/2009 09:09:23 --

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🌈 SEE ALSO 🌈

the SEE ALSO is literally just this link, bestie:

http://sourceforge.net/projects/mdtest

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xoxo, your Unix bestie 💖 this page is rockin' mdtest-1.8.3 and is dated 2010-05-05, so that's the version/date energy at the very end. 🫶✨