Sysbench fileio

[Rahul Raj]

HI,
I am running sysbench fileio for mysql with below command
./sysbench fileio --file-total-size=10G --file-test-mode=rndrw --time=300 --mysql-db=mysql --mysql-host=localhost --mysql-user=root prepare

It generated 128 intermediate test_file.0 , and so on test_file.128.
when I opened these files it shows only character ^@ which is 0x0 means null.

Is all these files are valid? why it is having only NULL character. Could anyone explain it.

When I run it, it is giving all the values as shown below.
./sysbench fileio --file-total-size=10G --file-test-mode=rndrw --time=300 --mysql-db=mysql --mysql-host=localhost --mysql-user=root run
Running the test with following options:
Number of threads: 1
Initializing random number generator from current time

Extra file open flags: (none)
128 files, 80MiB each
10GiB total file size
Block size 16KiB
Number of IO requests: 0
Read/Write ratio for combined random IO test: 1.50
Periodic FSYNC enabled, calling fsync() each 100 requests.
Calling fsync() at the end of test, Enabled.
Using synchronous I/O mode
Doing random r/w test
Initializing worker threads…

Threads started!

Throughput:
read: IOPS=157.09 2.45 MiB/s (2.57 MB/s)
write: IOPS=104.73 1.64 MiB/s (1.72 MB/s)
fsync: IOPS=335.32

Latency (ms):
min: 0.00
avg: 1.67
max: 139.93
95th percentile: 10.84
sum: 299863.61