[Lse-tech] Re: ext3 performance bottleneck as the number of spindles gets large

[Duc Vianney <dvianney@us.ibm.com>]

Andrew Morton wrote:
>If you have time, please test ext2 and/or reiserfs and/or ext3
>in writeback mode.
I ran IOzone on ext2fs, ext3fs, JFS, and Reiserfs on an SMP 4-way
500MHz, 2.5GB RAM, two 9.1GB SCSI drives. The test partition is 1GB,
test file size is 128MB, test block size is 4KB, and IO threads varies
from 1 to 6. When comparing with other file system for this test
environment, the results on a 2.5.19 SMP kernel show ext3fs is having
performance problem with Writes and in particularly, with Random Write.
I think the BKL contention patch would help ext3fs, but I need to verify
it first.

The following data are throughput in MB/sec obtained from IOzone
benchmark running on all file systems installed with default options.


Kernels           2519smp4   2519smp4   2519smp4   2519smp4
No of threads=1   ext2-1t    jfs-1t     ext3-1t    reiserfs-1t

Initial write     138010     111023      29808      48170
Rewrite           205736     204538     119543     142765
Read              236500     237235     231860     236959
Re-read           242927     243577     240284     242776
Random read       204292     206010     201664     207219
Random write      180144     180461       1090     121676

No of threads=2  ext2-2t     jfs-2t     ext3-2t    reiserfs-2t

Initial write     196477     143395      62248      55260
Rewrite           261641     261441     126604     205076
Read              292566     292796     313562     291434
Re-read           302239     306423     341416     303424
Random read       296152     295430     316966     288584
Random write      253026     251013        958     203358

No of threads=4  ext2-4t     jfs-4t    ext3-4t     reiserfs-4t

Initial write      79513     172302      42051      48782
Rewrite           256568     269840     124912     231395
Read              290599     303669     327066     283793
Re-read           289578     303644     327362     287531
Random read       354011     353455     353806     351671
Random write      279704     279922       2482     250498

No of threads=6  ext2-6t     jfs-6t    ext3-6t     reiserfs-6t

Initial write      98559      69825      59728      15576
Rewrite           274993     286987     126048     232193
Read              330522     326143     332147     326163
Re-read           339672     328890     333094     326725
Random read       348059     346154     347901     344927
Random write      281613     280213       3659     227579

Cheers,
Duc J Vianney, dvianney@us.ibm.com
home page: http://www-124.ibm.com/developerworks/opensource/linuxperf/
project page: http://www-124.ibm.com/developerworks/projects/linuxperf