What is the Number of Threads option, "sqlio -t"?

The Number of Threads option, "sqlio -t", specifies how many threads to use to perform test runs.

The default value is "-t1", 1 thread only. In this case, test runs are performed sequentially, there shouldn't be any performance impact on data blocking among threads.

Example 1 - Run SQLIO with 1 thread:

C:\fyicenter\SQLIO>sqlio -t1

1 thread reading for 30 secs from file testfile.dat
        using 2KB IOs over 128KB stripes with 64 IOs per run
initialization done
CUMULATIVE DATA:
throughput metrics:
IOs/sec:  2890.22
MBs/sec:     5.64

Example 2 - Run SQLIO with 2 threads:

C:\fyicenter\SQLIO>..\sqlio -t2

2 threads reading for 30 secs from file testfile.dat
        using 2KB IOs over 128KB stripes with 64 IOs per run
initialization done
CUMULATIVE DATA:
throughput metrics:
IOs/sec: 17921.66
MBs/sec:    35.00

Example 3 - Run SQLIO with 4 threads:

C:\fyicenter\SQLIO>..\sqlio -t4

4 threads reading for 30 secs from file testfile.dat
        using 2KB IOs over 128KB stripes with 64 IOs per run
initialization done
CUMULATIVE DATA:
throughput metrics:
IOs/sec: 20581.05
MBs/sec:    40.19

As you can see, when more threads are used, the throughput goes up, because more I/O tests can be performed with more threads running.

⇒ "sqlio -B" - Hardware/Software Buffering

⇐ "sqlio -i" - Number of IOs per IO Run

⇑ Getting Started with Microsoft SQLIO

⇑⇑ SQLIO Disk I/O Benchmark Test Tutorials