Linux RAID mdraid "stripe_cache_size" vs. transfer rate

Part of the Linux RAID mdraid RAID6 & RAID5 benchmarks, and Linux RAID mdraid RAID10, RAID0 benchmarks (continued) series.

"stripe_cache_size" vs. transfer rate

Generated with the following shell script:

#!/bin/bash
for cache_size in 256 512 768 1024 2048 4096 8192 16834 32768; do
 for i in {1..3}; do
 echo ${cache_size} > /sys/block/md0/md/stripe_cache_size
 sync
 echo 3 > /proc/sys/vm/drop_caches
 echo "stripe_cache_size: ${cache_size} (${i}/3)"
 # for write
 dd if=/dev/zero of=/dev/md0 bs=3145728 count=5460
 # for read
 dd if=/dev/md0 of=/dev/null bs=3145728 count=5460
 done
done

Linux RAID mdraid RAID6 & RAID5 benchmarks

Building a new file server, and thought I should post some benchmarks with mdraid RAID6 and RAID5 on Ubuntu 9.10 AMD64 with XFS, specifications for the machine are as follows:

Specifications

Intel Pentium D E6300 2.80Ghz
Gigabyte P45-UD3P
2 2GB DDR2-800 CL5 (4GB total)
6 1.5TB WDC Green 7200RPM (WD15EADS) on ICH10R (mdraid)
1 250GB Seagate 7200RPM (ST3250410AS) on JMicron JMB363

The mdraid will be run on the ICH10R, and the boot device (and operating sytsem) on the JMicron controller. Here are the benchmark results. All are using default XFS settings, benchmarks taken with bonnie++.

RAID6 mdraid Benchmarks

RAID6 mdraid Benchmarks

RAID6 64k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 88390  99 175541  25 88470  17 51515  80 289555  27 389.0   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  2419  15 +++++ +++  1219   5  1502   9 +++++ +++   920   4
devil2,8G,88390,99,175541,25,88470,17,51515,80,289555,27,389.0,0,16,2419,15,+++++,+++,1219,5,1502,9,+++++,+++,920,4

RAID6 128k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 88849  99 174076  24 84382  15 58716  80 291795  27 406.7   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  1254   4 +++++ +++   619   2   802   2 +++++ +++   668   2
devil2,8G,88849,99,174076,24,84382,15,58716,80,291795,27,406.7,0,16,1254,4,+++++,+++,619,2,802,2,+++++,+++,668,2

RAID6 256k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 82659  92 89437  12 64420  11 85758  95 214792  19 368.5   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  1237   6 +++++ +++   697   4   812   3 +++++ +++   673   3
devil2,8G,82659,92,89437,12,64420,11,85758,95,214792,19,368.5,0,16,1237,6,+++++,+++,697,4,812,3,+++++,+++,673,3

RAID6 512k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 88844  99 125203  17 70935  12 76991  91 288147  26 402.1   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  2231  11 +++++ +++   820   3  1669   7 +++++ +++   808   3
devil2,8G,88844,99,125203,17,70935,12,76991,91,288147,26,402.1,0,16,2231,11,+++++,+++,820,3,1669,7,+++++,+++,808,3

RAID5 mdraid Benchmarks

RAID5 mdraid Benchmarks

RAID5 64k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 88705  99 211212  30 103889  20 49043  75 360385  29 406.8   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  1081   2 +++++ +++   646   1   889   2 +++++ +++   634   1
devil2,8G,88705,99,211212,30,103889,20,49043,75,360385,29,406.8,0,16,1081,2,+++++,+++,646,1,889,2,+++++,+++,634,1

RAID5 128k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 88323  99 193034  28 101348  19 58707  79 337775  30 380.5   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  1086  14 +++++ +++   683   3   917   3 +++++ +++   586   1
devil2,8G,88323,99,193034,28,101348,19,58707,79,337775,30,380.5,0,16,1086,14,+++++,+++,683,3,917,3,+++++,+++,586,1

RAID5 256k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 88898  99 188605  26 92387  16 68355  86 357395  32 395.7   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16   888   1 +++++ +++   660   2   820   1 +++++ +++   570   1
devil2,8G,88898,99,188605,26,92387,16,68355,86,357395,32,395.7,0,16,888,1,+++++,+++,660,2,820,1,+++++,+++,570,1

RAID5 512k

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
devil2           8G 88868  99 147612  21 80418  13 80604  93 411211  36 387.4   0
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16   888   1 +++++ +++   613   1   855   1 +++++ +++   610   1
devil2,8G,88868,99,147612,21,80418,13,80604,93,411211,36,387.4,0,16,888,1,+++++,+++,613,1,855,1,+++++,+++,610,1

Overall RAID mdraid Benchmarks

Overall RAID mdraid Benchmarks