How do I characterize my usecase so that I can simulate it with fio the closest?

How do I characterize my usecase so that I can simulate it with fio the closest?

[Giuliano G Motter]

Hello all,

The company I work with uses USB Sticks as a crucial part of the
product and I was assigned a task to bring up a pragmatic method to
characterize USB Sticks from different models/vendors/manufacturers.

I intend to write a simple pytest based framework that will use fio to
characterize the USB sticks systematically.
This would allow me to perform hundreds of tests in sampled devices to
either approve or reprove that model/vendor/manufacturer, based on the
performance parameters.

To start with, I plan to perform a series of synthetic tests - where I
don't intend to simulate the real use case, but rather, just to
compare different device's performances against each other in a
handful of made-up stress scenarios.

At a second moment, tough, I would in fact like to implement a test
that is the closest as possible to the real process we have during USB
stick flashing

Question:
How do I characterize my use case so that I can simulate it with fio?

My process is something like "./proprietary_script.sh --device
/dev/sdc", where "proprietary_script.sh" is a single threaded app that
mounts the USB Stick and performs a series of copies (with cp) from
the host's SSD to the USB Stick fs.

How can I know what are the values of IO type, IO engine, IO size,
block size, etc to call fio with, so that fio will simulate my process
the closest? How can I gather such information?

By the way, the OS is a Ubuntu 14.

Thank you!

Giuliano Galhardi Motter
mottergiuliano@gmail.com

Re: How do I characterize my usecase so that I can simulate it with fio the closest?

[Jeff Moyer]

Giuliano G Motter <mottergiuliano@gmail.com> writes:

> At a second moment, tough, I would in fact like to implement a test
> that is the closest as possible to the real process we have during USB
> stick flashing
>
> Question:
> How do I characterize my use case so that I can simulate it with fio?

Have you tried the btrecord and btreplay utilities shipped with
blktrace?  Or, if you are set on using fio, you can replay blktraces
using fio.  See the fio(1) man page section on "I/O replay".

Good luck,
Jeff