Ingo, you said you were interested in slowdowns relative to 2.2, it
doesnt look good for reads, 2.2 looks to be 4-6 times faster than
2.4-test1, does this indicate there is something wrong somewhere?
There wasnt much difference with the -B5 patch, but from the looks of it
the patch effected raid1 and raid5 mainly.
I would love to track down bottlenecks and investigate kernel
limitations of software raid, i know that raid0 doesnt scale very well,
the more drives you add the less performance gain there is, im not sure
where to start looking to indentify why performance doesnt scale, any
advice anyone ?
Does this elevator stuff in 2.4 need "fine-tuning" to get better
performance ?
If anyone would like to see any other tests let me know.
SYSTEM
dual 433 celeron on bp6 with 128MB sdram, raid comprised of four 7200RPM
UDMA66 drives (2xIBM and 2xquantum) under two pci promise UDMA66
controllers. Individually the drives get 18-20 MB/s
TEST METHODS
I used three tests, dd, bonnie++ and tiobench.pl
to dd test writes i do
time dd if=/dev/zero of=./test bs=16k count=50000
to dd test reads i do
time dd if=./test of=/dev/null bs=16k count=50000
tiobench.pl -s=800
bonnie++ -s 800 -r 128
RESULTS
2.2.16+ide+raid-A0 - 4-way raid0 - Manual tests
Config Real User Sys
write 22.032 0.180 10.72 ~35MB/s
read 13.548 0.100 8.020 ~60MB/s
2.2.16 - 4-way raid0 - Bonnie++
Version 1.00a ------Sequential Output------ --Sequential Input-
--Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block--
--Seeks--
Machine MB K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP
/sec %CP
Unknown 800 6744 99 36330 50 17736 50 7194 98 64927 85
22.9 0
------Sequential Create------ --------Random
Create--------
-Create-- --Read--- -Delete-- -Create-- --Read---
-Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
/sec %CP
30 124 99 364 99 5125 99 125 99 453 99
362 85
Unknown,800,6744,99,36330,50,17736,50,7194,98,64927,85,22.9,0,30,124,99,364,99,5125,99,125,99,453,99,362,85
2.2.16+ide+raid-A0 - 4-way raid0 - tiobench
Size is MB, BlkSz is Bytes, Read, Write, and Seeks are MB/sec
File Block Num Seq Read Rand Read Seq Write Rand
Write
Dir Size Size Thr Rate (CPU%) Rate (CPU%) Rate (CPU%) Rate
(CPU%)
------- ------ ------- --- ----------- ----------- -----------
-----------
. 800 4096 1 65.16 58.1% 0.586 1.23% 32.28 44.7% 3.236
9.73%
. 800 4096 2 47.18 48.5% 0.709 1.86% 32.00 63.7% 3.199
12.4%
. 800 4096 4 39.38 41.3% 0.834 2.06% 32.09 73.2% 3.121
12.7%
. 800 4096 8 35.29 40.0% 0.946 2.24% 31.90 77.7% 3.048
13.4%
Under 2.4.0test1-ac15
2.4.0test1-ac15 - 4-way raid0 - DD test
Config Real User Sys
write 22.401 0.170 12.300 ~35MB/s
read 52.356 0.150 16.410 ~15MB/s
2.4.0test1-ac15 - 4-way raid0 - bonnie++ test
Version 1.00a ------Sequential Output------ --Sequential Input-
--Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block--
--Seeks--
Machine MB K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP
/sec %CP
Unknown 800 6823 99 35824 56 9584 28 5330 80 15657 36
17.2 0
------Sequential Create------ --------Random
Create--------
-Create-- --Read--- -Delete-- -Create-- --Read---
-Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
/sec %CP
30 121 99 +++++ 93 5656 99 122 99 +++++ 103
625 97
Unknown,800,6823,99,35824,56,9584,28,5330,80,15657,36,17.2,0,30,121,99,+++++,93,5656,99,122,99,+++++,103,625,97
2.4.0test1-ac15 - 4-way raid0 - tiobench test
Size is MB, BlkSz is Bytes, Read, Write, and Seeks are MB/sec
File Block Num Seq Read Rand Read Seq Write Rand
Write
Dir Size Size Thr Rate (CPU%) Rate (CPU%) Rate (CPU%) Rate
(CPU%)
------- ------ ------- --- ----------- ----------- -----------
-----------
. 800 4096 1 16.01 31.7% 0.575 1.06% 33.24 52.5% 2.050
3.28%
. 800 4096 2 8.468 17.6% 0.687 1.43% 33.34 63.8% 2.138
3.69%
. 800 4096 4 6.687 13.3% 0.795 1.66% 33.26 67.7% 2.187
4.29%
. 800 4096 8 6.064 11.5% 0.889 1.82% 33.12 70.9% 2.241
4.59%
2.4.0test1-ac15-B5 - 4 way raid0 - DD test
mode Real User Sys
write 22.504 0.180 12.280 ~35MB/s
read 52.205 0.070 17.530 ~15MB/s
2.4.0test1-ac15-B5 - 4 way raid0 - bonnie++ test
Version 1.00a ------Sequential Output------ --Sequential Input-
--Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block--
--Seeks--
Machine MB K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP
/sec %CP
Unknown 800 6836 99 36001 55 9916 28 5307 78 15868 36
17.3 0
------Sequential Create------ --------Random
Create--------
-Create-- --Read--- -Delete-- -Create-- --Read---
-Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
/sec %CP
30 121 99 +++++ 96 5635 99 122 99 +++++ 97
631 97
Unknown,800,6836,99,36001,55,9916,28,5307,78,15868,36,17.3,0,30,121,99,+++++,96,5635,99,122,99,+++++,97,631,97
2.4.0test1-ac15-B5 - 4-way raid0 - tiobench test
Size is MB, BlkSz is Bytes, Read, Write, and Seeks are MB/sec
File Block Num Seq Read Rand Read Seq Write Rand
Write
Dir Size Size Thr Rate (CPU%) Rate (CPU%) Rate (CPU%) Rate
(CPU%)
------- ------ ------- --- ----------- ----------- -----------
-----------
. 800 4096 1 15.26 33.7% 0.561 1.22% 33.25 51.8% 2.071
4.64%
. 800 4096 2 8.402 18.1% 0.678 1.56% 33.48 64.1% 2.132
5.25%
. 800 4096 4 7.021 14.2% 0.789 1.76% 33.40 68.5% 2.194
5.10%
. 800 4096 8 6.248 12.0% 0.885 1.98% 33.25 71.5% 2.237
5.40%
Thats it for now
Glenn
