Dell POWEREDGE R720XD User Manual

Page 36

Advertising
background image

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

36

IOzone Argument

Description

-t

Number of threads

+m

Location of clients to run IOzone on 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 256G (number of clients * file size per client = 256G).

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 4G file. The record size used for the random tests
was 4k 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.

Advertising
This manual is related to the following products: