IOzone的输出中的“Min xfer”和“吞吐量”是什么意思

Question

我是IOzone的新用户，当我用命令./iozone -i 0 -i 1 -t 2 -T运行IOzone时，它会生成以下结果（部分）：

Command line used: ./iozone -i 0 -i 1 -t 2 -T 
Output is in Kbytes/sec 
Time Resolution = 0.000001 seconds. 
Processor cache size set to 1024 Kbytes. 
Processor cache line size set to 32 bytes. 
File stride size set to 17 * record size. 
Throughput test with 2 threads 
Each thread writes a 512 Kbyte file in 4 Kbyte records 

Children see throughput for 2 initial writers = 650943.69 KB/sec 
Parent sees throughput for 2 initial writers = 13090.24 KB/sec 
Min throughput per thread   = 275299.72 KB/sec 
Max throughput per thread   = 375643.97 KB/sec 
Avg throughput per thread   = 325471.84 KB/sec 
Min xfer     =  356.00 KB 

Children see throughput for 2 rewriters = 1375881.50 KB/sec 
Parent sees throughput for 2 rewriters  = 10523.74 KB/sec             
Min throughput per thread   = 1375881.50 KB/sec 
Max throughput per thread   = 1375881.50 KB/sec 
Avg throughput per thread   = 687940.75 KB/sec 
Min xfer     =  512.00 KB 

Children see throughput for 2 readers  = 2169601.25 KB/sec 
Parent sees throughput for 2 readers  = 27753.94 KB/sec 
Min throughput per thread   = 2169601.25 KB/sec 
Max throughput per thread   = 2169601.25 KB/sec 
Avg throughput per thread   = 1084800.62 KB/sec 
Min xfer     =  512.00 KB 

Children see throughput for 2 re-readers = 2572435.25 KB/sec 
Parent sees throughput for 2 re-readers  = 26311.78 KB/sec 
Min throughput per thread   = 2572435.25 KB/sec 
Max throughput per thread   = 2572435.25 KB/sec 
Avg throughput per thread   = 1286217.62 KB/sec 
Min xfer     =  512.00 KB 

iozone test complete. 

我弄不清楚“吞吐量”和“闽XFER”的意​​思是有一个人能帮助我吗？ 顺便说一句，为什么儿童和父母的吞吐量不同？谢谢！

Answer 1

Min xfer指的是一次写入的最小数据量。 “每个线程在4千字节记录中写入一个512 KB文件”

因此，如果Min xfer是512.00 KB，它会立即将所有实际文件写入磁盘（将所有4 Kbyte记录组合在一起）。

由于操作系统I/O缓冲，孩子和父母吞吐量不同。 iozone不强制直接（非缓冲）读取或写入吞吐量测试。你真正测试的是你的系统的缓冲区缓存+磁盘缓存+磁盘速度组合。