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Dell HPC NFS Storage Solution - High Availability (NSS-HA) Configuration with Dell PowerVault
MD3260/MD3060e Storage Arrays
23
IOzone Argument
Description
-s
File size.
-t
Number of threads.
+m
Location of clients to run IOzone when in clustered
mode.
-w
Does not unlink (delete) temporary file.
-I
Use O_DIRECT, bypass client cache.
-O
Give results in ops/sec.
For the sequential tests, file size was varied along with the number of clients such that the total
amount of data written was 256GiB (number of clients * file size per client = 256GiB).
IOzone Sequential Writes
# /usr/sbin/iozone -i 0 -c –e –w –r 1024k –s 4g –t 64 -+n -+m ./clientlist
IOzone Sequential Reads
# /usr/sbin/iozone -i 1 -c -e -w -r 1024k -s 4g -t 64 -+n -+m ./clientlist
For the random tests, each client read or wrote a 4GiB file. The record size used for the random tests
was 4KiB to simulate small random data accesses.
IOzone IOPs Random Access (Reads and Writes)
# /usr/sbin/iozone -i 2 -w -r 4k -I -O -w -+n -s 4g -t 1 -+m ./clientlist
By using -c and -e in the test, IOzone provides a more realistic view of what a typical application is
doing. The O_Direct command line parameter allows us to bypass the cache on the compute node on
which we are running the IOzone thread.