PR SM
1
PR SM Laboratory A Parameter Extraction Tool for Windows A Parameter Extraction Tool for Windows I/O System Characterization I/O System Characterization Versailles Saint Quentin University National Scientific research center Jalil BOUKHOBZA The Problem Statement I/Os are critical. Windows OS Vaguely documented Sources are not available Poorly studied in academic research Hardware manufacturer’s documentation not sufficient for completely understanding a given I/O system and simulating it. The Objectives Understanding I/O flow and Performance in Windows systems. Making possible accurate simulations of the Windows I/O subsystem: From the application -> Disk mechanical movements Contributions Windows I/O performance measurement Windows I/O performance measurement tool : tool : Measure I/O performance of a given architecture on a Windows OS (2000, XP, 2003) Empirical I/O parameters extraction Empirical I/O parameters extraction tool : tool : Get the parameters defining the I/O subsystem to: Understand the resultant performance Build accurate simulations Windows I/O Performance Measurements Windows file access modes (Win32 CreateFile()) Normal, sequential, random, no buffer, write through Request sizes Sequential / Random (accesses) Results: I/O throughput Response times File system driver Storage Device driver Storage Device Cache manager Virtual memory manager I/O request FastIO Page fault R ead transferrates fordifferentm odes 0 5 10 15 20 25 30 35 40 45 50 0 100 200 300 400 500 600 R equestsizes (K B ) T ran sfer rates (M B /sec 1-N o buffer 2-N orm al 3-S equential 1 2 3 N orm al m ode read fordifferentrequestsizes 0 5 10 15 20 25 30 35 0 10 20 30 40 Requestnum ber R esp on se tim es ( 512KB 64KB 320KB Read transfer rates and response times Example of execution Configuration: Empirical I/O Parameter Extraction File system cache -> process memory throughput (1) Disk cache -> process memory throughput (2) Seek times Track sizes (zoning) Disk cache segment size and number Disk cache algorithms Process Memory File system Cache memory Disk Disk cache Measuring throughputs 1 2 Example: Conclusions A Windows dedicated I/O performance measurement tool taking into account the different access modes (using different prefetching algorithms for read / write operations). Very easy to use tool to get I/O parameters. The extracted parameters allow to run accurate simulations less then 4% variation compared to real measures for response times and throughputs. Under development Allowing asynchronous file accesses Injecting inter arrival times More control on request sequentiality Testing more architectures References Some Studies on Windows I/Os [1] E.Riedel, C.VanIngen, J.Gray “A performance study of sequential I/O on WindowsNT4”, 2nd USENIX WindowsNT Symposium, WA, 1998. [2] L.Chung, J.Gray, B.Worthington, R.Horst, Windows2000 disk I/O performance, Technical report MS-TR-2000-55, Micros [3] J. Boukhobza, C. Timsit, “On Windows File Access modes: a Performance Study”, to appear in the proceeding of WISIC Cape Town, South Africa, January 2005. About Windows internals [4] D.A.Solomon, M.E.Russinovich, Inside Windows2000, Redmond, Washington, Microsoft Press, 2000. Caching policies [5] N.C Burnett, J. Bent, A.C. Arpaci-Dusseau, R.H. Arpaci-Dusseau, “Exploiting Gray-Box knowledge of Buffer-cache mana proceeding of USENIX 2002 Annual Technical conference , Monterey, California, USA, June 2002. Windows I/O simulations [6] J. Boukhobza, C. Timsit, “An I/O Simulator for Windows Systems”, to appear in ESMc2004 proceeding, Paris, France, O N o bufferm ode read of64K B 0 0.5 1 1.5 2 2.5 0 5 10 15 20 25 30 Requestnum ber Response tim e(m s) Seek times Study the periodicity to find track size Per request response time Cache segment size Read block of size T from disk Re-read that block: if entirely loaded from the disk cache -> segment size T, increment T else ≥ decrement T Empty the cache Systematic global performance measuring tool Automatic parameter extraction Storage architecture I/O sequence strategy defined by the user or real workload traces Measuring Tools Behavior of the storage system for the specified I/O strategy Performance of the storage system for read/write operation I/O Generator Simulation Tool 1 2 3 Disk cache updating algorithms Generally simple algorithms (LRU, FIFO, LFU, etc.) that can be tested once the segment size known by issuing different read block sequences and then re-read the blocks to see which one is accessed from the disk (and so has been ejected from the cache). Using flags of the CreateFile() function 1 2 3 4 5 6 7 8 Processor IntelPentium 4 1,8GHz 256M B RDRAM Disk Fujitsu M A N 3184M P Capacity Rotation Seek Interface 18,4 GBytes 10025 rpm track to track 0,4/0,6m s U ltra 160 SCSI D isk Cache Track size average 4,5 /5m s 8M B 221K B/377K B FullStroke 11 /12m s Software W indows2000 Professional5.00.2195 Service Pack 3 File sysem FA T32 4 MASCOTS 2004
description
PR SM. Versailles Saint Quentin University. Laboratory. National Scientific research center. File system Cache memory. Process Memory. Disk cache. Disk. I/O Generator. Simulation Tool. I/O request. FastIO. 4. File system driver. Storage Device driver. Cache manager. - PowerPoint PPT Presentation
Transcript of PR SM
PR SMLaboratory
A Parameter Extraction Tool for Windows I/O System A Parameter Extraction Tool for Windows I/O System
CharacterizationCharacterization
Versailles Saint Quentin University
National Scientific research center
Jalil BOUKHOBZA
The Problem Statement
I/Os are critical. Windows OS Vaguely documented
Sources are not available Poorly studied in academic research
Hardware manufacturer’s documentation not sufficient for completely understanding a given I/O system and simulating it.
The Objectives
Understanding I/O flow and Performance in Windows systems. Making possible accurate simulations of the Windows I/O subsystem:
From the application -> Disk mechanical movements
Contributions
Windows I/O performance measurement tool : Windows I/O performance measurement tool : Measure I/O performance of a given architecture on a Windows OS (2000, XP, 2003)
Empirical I/O parameters extraction tool :Empirical I/O parameters extraction tool :
Get the parameters defining the I/O subsystem to:
Understand the resultant performance
Build accurate simulations
Windows I/O Performance Measurements
Windows file access modes (Win32 CreateFile()) Normal, sequential, random, no buffer, write through
Request sizes Sequential / Random (accesses)
Results:
I/O throughput Response times
File system driver
Storage Device driver
Storage Device
Cache manager
Virtual memory manager
I/O requestFastIO
Page fault
Read transfer rates for different modes
0
5
10
15
20
25
30
35
40
45
50
0 100 200 300 400 500 600
Request sizes (KB)
Tra
ns
fer
rate
s (
MB
/se
c)
1- No buffer 2- Normal 3- Sequential
1
2
3
Normal mode read for different request sizes
0
5
10
15
20
25
30
35
0 10 20 30 40Request number
Resp
on
se t
imes (
ms)
512KB 64KB 320KB
Read transfer rates and response times
Example of execution
Configuration:
Empirical I/O Parameter Extraction
File system cache -> process memory throughput (1) Disk cache -> process memory throughput (2) Seek times Track sizes (zoning) Disk cache segment size and number Disk cache algorithms
Process Memory
File system Cache memory Disk
Disk cache
Measuring throughputs1
2
Example:
Conclusions
A Windows dedicated I/O performance measurement tool taking into account thedifferent access modes (using different prefetching algorithms for read / write operations). Very easy to use tool to get I/O parameters. The extracted parameters allow to run accurate simulations less then 4% variation compared to real measures for response times and throughputs.
Under development
Allowing asynchronous file accesses Injecting inter arrival times More control on request sequentiality Testing more architectures
References
Some Studies on Windows I/Os[1] E.Riedel, C.VanIngen, J.Gray “A performance study of sequential I/O on WindowsNT4”, 2nd USENIX WindowsNT Symposium, Seattle, WA, 1998.[2] L.Chung, J.Gray, B.Worthington, R.Horst, Windows2000 disk I/O performance, Technical report MS-TR-2000-55, Microsoft Research, 2000.[3] J. Boukhobza, C. Timsit, “On Windows File Access modes: a Performance Study”, to appear in the proceeding of WISICT2005, Cape Town, South Africa, January 2005.About Windows internals[4] D.A.Solomon, M.E.Russinovich, Inside Windows2000, Redmond, Washington, Microsoft Press, 2000.Caching policies[5] N.C Burnett, J. Bent, A.C. Arpaci-Dusseau, R.H. Arpaci-Dusseau, “Exploiting Gray-Box knowledge of Buffer-cache management”, proceeding of USENIX 2002 Annual Technical conference, Monterey, California, USA, June 2002.Windows I/O simulations [6] J. Boukhobza, C. Timsit, “An I/O Simulator for Windows Systems”, to appear in ESMc2004 proceeding, Paris, France, October 2004.
No buffer mode read of 64KB
0
0.5
1
1.5
2
2.5
0 5 10 15 20 25 30
Request number
Resp
onse
tim
e (m
s)
Seek times
Study the periodicity to find
track size
Per request response time
Cache segment sizeRead block of size T from disk
Re-read that block: if entirely loaded from the disk cache -> segment size ≥T, increment T else decrement T
Empty the cache
Systematic global performance measuring tool
Automatic parameter extraction
Storage architecture
I/O sequence strategy defined by the user or real workload traces
Measuring Tools
Behavior of the storage system for the specified I/O strategy
Performance of the storage system for read/write operation
I/O Generator
Simulation Tool
1 2
3
Disk cache updating algorithmsGenerally simple algorithms (LRU, FIFO, LFU, etc.) that can be tested once the segment size known by issuing different read block sequences and then re-read the blocks to see which one is accessed from the disk (and so has been ejected from the cache).
Using flags of the CreateFile() function
1 2
3 4
5 6
7 8
Processor Intel Pentium4 1,8GHz 256MB RDRAMDisk Fujitsu MAN 3184MP Capacity Rotation Seek
Interface 18,4 GBytes 10025 rpm track to track 0,4/0,6msUltra 160 SCSI Disk Cache Track size average 4,5 / 5ms
8MB 221KB/377KB Full Stroke 11 / 12msSoftware Windows2000 Professional 5.00.2195 Service Pack 3 File sysem FAT324
MASCOTS 2004
