系统技术非业余研究

IOzone官网: http://www.iozone.org/
IOzone is a filesystem benchmark tool. The benchmark generates and measures a variety of file operations. Iozone has been ported to many machines and runs under many operating systems.

Benchmark Features:
* ANSII C source
* POSIX async I/O
* Mmap() file I/O
* Normal file I/O
* Single stream measurement
* Multiple stream measurement
* Distributed fileserver measurements (Cluster)
* POSIX pthreads
* Multi-process measurement
* Excel importable output for graph generation
* Latency plots
* 64bit compatible source
* Large file compatible
* Stonewalling in throughput tests to eliminate straggler effects
* Processor cache size configurable
* Selectable measurements with fsync, O_SYNC
* Builds for: AIX, BSDI, HP-UX, IRIX, FreeBSD, Linux, OpenBSD, NetBSD, OSFV3, OSFV4, OSFV5, SCO OpenServer, Solaris, MAC OS X, Windows (95/98/Me/NT/2K/XP)

他的定位非常明确是针对文件系统的性能测试的。和常用的IO性能测试工具sysbench, fio, iometer不同, 它主要是通过模拟用户访问文件模式的不同，典型的如下面的几种：
(0=write/rewrite, 1=read/re-read, 2=random-read/write
3=Read-backwards, 4=Re-write-record, 5=stride-read, 6=fwrite/re-fwrite
7=fread/Re-fread, 8=random_mix, 9=pwrite/Re-pwrite, 10=pread/Re-pread
11=pwritev/Re-pwritev, 12=preadv/Re-preadv)
来达到隔离访问文件系统的meta信息和data信息的不同的开销， 从而反应文件系统的性能。

Ubuntu下可以用 apt-get -y install iozone安装就好。

他有二种模式： 1. 测试吞吐量模式。 2. 测试文件系统对记录大小，文件大小不同组合的反应。

以下是我用过的测试吞吐量模式的参数:
iozone -t -l 1 -u 16 -L 64 -S 8192 -b fio.xls -R -M -s 10G -r 32k -I -T -C -j 32 -+p 60
参数解释
-t -> Throughput test
-s 10G -> File size set to 18874368 KB
-M ->Machine = Linux my174.cm4 2.6.18-164.el5 #1 SMP Tue Aug 18 15:51:48 EDT 2009
-r ->32k Record Size 32 KB
-I ->O_DIRECT feature enabled
-S 8192 ->Processor cache size set to 8192 Kbytes.
-L 64 ->Processor cache line size set to 64 bytes.
-j 32 ->File stride size set to 32 * record size.
-l 1 ->Min thread = 1
-u 16 ->Max thread = 16
-R ->Excel chart generation enabled
-b fio.xls ->产生的二进制格式execl文件名
-+p 60 ->Percent read in mix test is 60

测试文件系统对记录大小，文件大小不同组合的反应时候的参数：
TODO

玩的开心。