Small-file Random Create and Write/Read Comparison

Test bed:

Kernel: 2.6.26-rc2 and ext4-patch-queue-c23f8dd92fe816954b102d8a892276f17440159a (update of May 20, 2008)

Partition size: 5 TB (IBM DS4100 Storage System with 400GB SATA 7200rpm disks)
IO scheduler: CFQ

Tests are done on a bi-Xeon machine with 2G of RAM and with hyper-threading enabled (-> 4 CPUs).

processor      : 4
vendor_id      : GenuineIntel
cpu family     : 15
model          : 4
model name     : Intel(R) Xeon(TM) CPU 2.80GHz
cpu MHz        : 2793.078
cache size     : 1024 KB
bogomips       : 5586.59

#hdparm -t /dev/md0

/dev/md0:
Timing buffered disk reads: 332 MB in 3.00 seconds = 110.51 MB/sec

e2fsprogs used: 1.41-WIP from the "next" branch of e2fsprogs git tree (update of May 20, 2008)

Synopsis:

FFSB filesystem benchmarking software 5.1 available at

http://sourceforge.net/projects/ffsb/

ffsb profile used:

num_filesystems=1
num_threadgroups=1
directio=0
time=1800

[filesystem0]
        location=/mnt/test/
        num_files=5000
        num_dirs=1000
        max_filesize=524288
        min_filesize=4096
[end0]

[threadgroup0]
        num_threads=128
        write_size=4096
        write_blocksize=4096
        read_blocksize=4096
        create_weight=1
        write_weight=1
        readall_weight=2
[end0]

This profile runs 128 threads which do a combination of small file creates, reads and writes.
We collect the throughput scores and the CPU utilization values given by ffsb output.

The partition used is formated with mkfs and mounted with appropriate options before each run of ffsb. A FS check is done after each run.

The script used is available here.

Results


	mkfs options	mount options	Transactions per second	CPU usage %	e2fsck elapsed time in seconds
ext3	-I 256	data=writeback	7090	8.6	4004
xfs		"defaults"	(1)
ext4	-I 256	data=writeback	7898	7.2	2593
	-I 256	data=writeback, nodelalloc	9491	13.1	2827
	-I 256 -O uninit_groups	data=writeback	7194	7.5	257
	-I 256 -O uninit_groups	data=writeback, nomballoc	7268	7.5	279
	-I 256 -O uninit_groups	data=writeback, nomballoc,nodelalloc	6409	8.7	256
	-I 256 -O uninit_groups	data=writeback, journal_async_commit	7147	7.4	-
	-I 256 -Ouninit_groups,flex_bg -G 64	data=writeback	9906	9.1	245
	-I 256 -Ouninit_groups,flex_bg -G 64	data=writeback, nomballoc	10383	9.7	252
	-I 256 -Ouninit_groups,flex_bg -G 64	data=writeback, nomballoc,nodelalloc	10596	15.2	307
	-I 256 -Ouninit_groups,flex_bg -G 64	data=writeback, journal_checksum	9860	9.0	245
	-I 256 -Ouninit_groups,flex_bg -G 64	data=writeback, journal_async_commit	10373	10.0	-

(1) no result for xfs filesystem, the system hung.