ONTAP Discussions

sio_ntap usage


I am trying to use "sio_ntap" following the manual as follows with specified file.


sio 100 100 512 1m 60 1 filename1


but I got Error message like Ex) say.


I am wandering how I run command sio_ntap with specified files like manual.

Any help

Thank you.



Test Environment:RHEL 6.6



# ./sio_ntap_linux 100 0 8k 1m 10 1 /mnt/test

Version: 3.00
byte count mismatch: Success

sio_ntap: Error accessing file






the problem is that the file must exist - so if you want to test your netapp with the file "filename1" you need to put a file called "filename1" with at least 1mb on your filer and direct the sio_ntap to that path which is located on your filer - if you do this within a virtual machine that is located on the filer the path is irrelevant.


why do you use a file with 1mb? this seems very small to me.


following suggestion:

1. create an empty file (e.g. use notepad and save it as "filename1" - beware to remove extension!)

2. run sio in the following: sio_ntap.exe 0 0 32k 40g 180 30 filename1
- this would dump data (zeros) into the empty file, you created, for 180seconds - then it stops - even the file doesn't have 40g

3. the you can run sio to read: sio_ntap.exe 100 100 32k 20g 60 30 filename1

- i made the file a bit smaller otherwhise you'll get an error again - just have a look at your filename1 and take something smaller - also the time was reduced to 60sec. like you had it.


personally i would recommend the filesize should be bigger that the memory of the machine - otherwhise you could have the problem that the file is cached somehow by the OS - also the file should be re-created if you use in the same VM - same caching issue.

another thing to remind is that you can start sio mulitple times - you have configured 30threads - but 30 threads on one file and if your filer doesn't come to it's edge you possible won't see as many IOPS you wanted to - so e.g. start it 4 times the same time to four different files - if sio finishes - count the iops together and you'll know how much you can get out of your box with the given parameters.


beware on tests with SSD - they decrease in performance a bit over a half year of you have them in use (they are a bit overpowered when they come from factory).




First of all, apologize about replying very late.


thanks for your reply and suggestion.


As you mentioned, I created file with 1mb size and sio_ntap worked fine.

I just wanted to see how sio_ntap works so didn't care about file size.


>personally i would recommend the filesize should be bigger that the memory of the machine 


I have been working on the machine which has 192GB memory and

should I make a file bigger than 192GB as you say.

*I am working with file size 10GB.


Thank you 


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