Iometer: Why, What, Where, and How? Presented By Sohail Sarwar Supervisor Dr. Raihan Ur Rasool 1

Agenda Introduction What is Iometer Where employed Why Iometer How applied Conclusion Q& A 2

Introduction 3

Introduction-I Widening gulf between CPU & SSD speeds. CPU speed 50 % Vs SSD 8 % improvement. High IO intensive Systems. Page miss, IO latencies & wasted CPU cycles. Consequently Information Systems Consume more energy and Emit masses of CO2. Improving IO performance is imperative. Disparate efforts made to overcome IO problems. 4

Introduction-II SSD performance improvement efforts Caching Prefetching (based on Locality of Reference) Prefetching (based on AI techniques) Solid State Drives Some mechanism to measure the efficacy of emerging products & techniques The most common measure is the IO performance Various Tools available e.g. Winbench, IPeak Iometer is the most comprehensive one 5

What is Iometer??

Iometer-I An open source tools used to emulate the disk or network I/O load of any program or benchmark Examines and records the performance of I/O operations and their impact on the system Iometer is an I/O subsystem measurement and typographical tool. Equips user with Workload generator (to stress the system) Measurement tool (examines and records the IO performance ) Works for both for single and clustered systems. Usable in Windows as well as Linux environment 7

Iometer-II Iometer can be used for measurement and characterization System-level hard drive performance. CPU utilizations System-level network performance. Performance of disk and network controllers. Bandwidth and latency capabilities of buses. Network throughput to attached drives. Error in Reading and writing. 8

Iometer-III By Using Iometer ’s GUI, we configure The workload. Set operating parameters. Start and stop tests. Instruct Dynamo what to do? Collects the resulting data. Summarizes the results in output files. Only one copy of Iometer be running at a time. Typically deployed on the server machine. 9

Dynamo-I Dynamo is the workload generator having no user interface. At Iometer ’s command, Dynamo performs I/O operations Records performance information, Returns the data to Iometer. More than one copy of Dynamo can run at a time One copy runs on each client machine. 10

Dynamo-II Dynamo is multithreaded component. Each copy can simulate the workload of multiple client programs. Each running copy of Dynamo is called a ‘Manager’. Each thread within a copy of Dynamo is called a ‘worker’. 11

Installing Iometer Download the Iometer package & uncompress the files Place the files Iometer.exe and Dynamo.exe in the same directory. (Valid for prior versions) In order to execute Dynamo on multiple machines, deploy Dynamo.exe on each machine. If Iometer and Dynamo run on a single system, no network required. 12

Execution of Iometer By executing Iometer.exe. Loading a saved setup file by double-clicking on an.icf file, Dragging an.icf Iometer.exe icon C:\> iometer myconfig.icf Generates results in.xls 13

How Iometer Applied??

To Start Test For Disk Performance Initiate Iometer ‘s main window. Manager (the name of the local computer) in the Topology panel. Select manager’s available disk drives appear in the Disk Targets tab. Blue icons-physical drives. Yellow icons-requires preparation. A yellow icon with a red slash. 15

Working Description of components 16

Topology and Disk targets 17

Access Specification 18

Access Specifications- Detailed 19

Test Setup 20

Results display 21

Result Display- Read Detail 22

Result Display- Write Detail 23

Another Result ‘s view 24

Dynamo 25

Process Whenever you start a test you will Specify the Target disk Select an appropriate Access specification Press ‘Green flag’ to start test Specify name of CSV file to store results Iometer will prepare the device for first time By creating test “iobw.tst” file 26

Other tools WinBench 99 (not comprehensive as Iometer) Sequential transfer rate, average random acc Xbench (specific to Mac OS) Xbench compares the relative speeds of two systems. Access time & CPU utilization. IOStone (for DOS, UNIX and OS/2 ) read/write troughput in kb/secenchmark No specific interface & GUI 27

Conclusions The Purpose and working of Iometer has been explained. How two components of Iometer work. Acquiring the results from.CSV files. Iometer found to be most suitable option due to GUI, workload generation & display Enhancement in upcoming versions can be observed on iometer.org. 28

Q&A 29

Thanx 30