HP IO Accelerator for BladeSystem c-Class Performance Tuning Manuel d'utilisateur Page 1

HP IO Accelerator Performance Tuning Guide Abstract This guide is designed to help verify and improve HP IO Accelerator performance. Part Number:

Debugging performance issues 10 Debugging performance issues Improperly configured benchmark Issue The most common issue in achieving performance wi

Debugging performance issues 11 Send the bundle to [email protected], and request assistance in debugging a performance issue. [Reviewers: how do

Debugging performance issues 12 IMPORTANT: Some PCI Express chips do not properly report PCIe errors, or they might report errors when none exist.

Debugging performance issues 13 Correctable Error Reporting: enabled Non-fatal Error Reporting: enabled Unsupported Request Reporting: e

Debugging performance issues 14 Benchmarking through a filesystem Issue Although using a filesystem is necessary for most storage deployments, it in

Debugging performance issues 15 to avoid this issue. For more information, see the patch (http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2

General tuning techniques 16 General tuning techniques Using direct I/O, unbuffered, or zero copy 10 Traditional I/O paths include the page cache, a

General tuning techniques 17 protocols and have long pipelines, the IO Accelerator does not suffer from major latency increases as the number of out

General tuning techniques 18 • Using the fio-format command to re-initialize the drive • Performing large sequential writes to the drive For more

General tuning techniques 19 NOTE: HP recommends using this option only with a 4 KiB sector size. Values Description <list of serial numbe

© Copyright 2011 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice. The only warranties

Tuning techniques for writes 20 Tuning techniques for writes Increased steady-state write performance with fio-format Under a sufficiently long sust

Linux filesystem tuning 21 Linux filesystem tuning ext2-3-4 tuning XFS is currently the recommended filesystem. It can achieve up to three times the

Linux filesystem tuning 22 (stride) 32K = 256K / 8K (dbd) 4 = 5 - 1 (stripe_width) 128 = 4 * 32K This results in the following command: $ mkfs.ext3

fio benchmark 23 fio benchmark Compiling the fio benchmark The fio benchmarking utility is used to verify Linux system performance with an IO Accele

Verifying IO Accelerator performance on Windows operating systems 24 Verifying IO Accelerator performance on Windows operating systems Using Iometer

Programming using direct I/O 25 Programming using direct I/O Using direct I/O on Linux Under Linux, the best way to enable direct I/O is on a per-fi

Programming using direct I/O 26 memset(buf, 0xaa, ps*256); if( (fd = open(FILENAME, O_WRONLY | O_DIRECT) ) < 0 ) { perror("Open failed"

Programming using direct I/O 27 int open(char* filename); int write(char* buf, int size_t); int close(); size_t gbytesWritten() { return bytes_writt

Programming using direct I/O 28 exit(ret); } do { ret = file.write(buf, bufsize); if( ret < 0 ) { cerr << endl << "Error writing

Windows driver affinity 29 Windows driver affinity Setting Windows driver affinity On a multiprocessor system, the operating system routes an I/O re

Contents 3 Contents Introduction ...

Windows driver affinity 30 • Buses 36 and 37 : Node 1 (processors 2 and 3) • Buses 82 and 86 : Node 2 (processors 4 and 5) • Buses 169 and 170 :

Acronyms and abbreviations 31 Acronyms and abbreviations AIO asynchronous input/output CPU central processing unit DMA direct memory access DRAM

Index 32 A About this guide 5 B benchmarking through filesystem 14 C C++ code sample 26 compiling fio benchmark 23 CP, using 14 CPU auto-i

Index 33 Windows driver affinity, setting 29 Windows system performance 9, 24 write bandwidth test 7 Z zero copy 10 16

Contents 4 Setting Windows driver affinity ...

Introduction 5 Introduction About the Performance and Tuning Guide Welcome to the Performance and Tuning Guide for the HP IO Accelerator. This guide

System performance 6 System performance Verifying Linux system performance To verify Linux system performance with an IO Accelerator, HP recommends

System performance 7 $ fio --filename=/dev/fioa --direct=1 --rw=randwrite --bs=4k --size=5G --numjobs=64 --runtime=10 --group_reporting --name=file1

System performance 8 READ: io=4,058MiB, aggrb= 414MiB/s, minb=414MiB/s, maxb=414MiB/s, mint=10036msec, maxt=10036msec Disk stats (read/write):

System performance 9 Starting 64 processes Jobs: 64 (f=64): [wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww] [100.0% done] [