aiol test doesn't increase aio-max-nr enough

[Jeff Lane ]

Noted this on a certification run for a Purley system:

Running stress-ng aiol stressor for 240 seconds....
stress-ng: info: [55752] dispatching hogs: 208 aiol
stress-ng: info: [55752] cache allocate: using built-in defaults as unable to determine cache details
stress-ng: info: [55752] cache allocate: default cache size: 2048K
stress-ng: error: [55831] stress-ng-aiol: io_setup failed, ran out of available events, consider increasing /proc/sys/fs/aio-max-nr, errno=11 (Resource temporarily unavailable)
stress-ng: error: [55832] stress-ng-aiol: io_setup failed, ran out of available events, consider increasing /proc/sys/fs/aio-max-nr, errno=11 (Resource temporarily unavailable)
<snip>
stress-ng: error: [55752] process [55959] (stress-ng-aiol) aborted early, out of system resources
stress-ng: error: [55752] process [55960] (stress-ng-aiol) aborted early, out of system resources
stress-ng: info: [55752] successful run completed in 242.79s (4 mins, 2.79 secs)
return_code is 3

I wonder if it's more apropos to increase aio-max-nr before testing, or have fwts (either by default or by optional arg) increase aio-max-nr temporarily at runtime.

https://certification.canonical.com/hardware/201708-25660/submission/121819/test/64283/result/9072357/

This is a Purley system running 4.4.0-91-generic 16.04 LTS

[Alex Hung (alexhung)]

You can increase aio-max-nr with simple commands (with root) such as

---------------------------------
# save & change aio-max-nr
TMP_AIO=`cat /proc/sys/fs/aio-max-nr`
echo 200000 > /proc/sys/fs/aio-max-nr

# doing some tests
...

# restore aio-max-nr
echo $TMP_AIO > /proc/sys/fs/aio-max-nr
---------------------------------

There is no need for fwts to support changing aio-max-nr.

[Colin Ian King (colin-king)]

I'm confused. Surely this is a bug against stress-ng and not fwts.

[Jeff Lane  (bladernr)]

On Wed, Sep 20, 2017 at 8:12 PM Colin Ian King <email address hidden>
wrote:

> I'm confused. Surely this is a bug against stress-ng and not fwts.
>
> ** Changed in: fwts
> Assignee: (unassigned) => Colin Ian King (colin-king)
>
> ** Changed in: fwts
> Importance: Undecided => Low
>
> ** Project changed: fwts => stress-ng

Oh man, you're absolutely right Colin. I have no idea why I filed that
under FWTS...

Thanks for changing it to the right package for me.
--
Sent from my iPhone so please forgive any typos, top posting and such.

[Colin Ian King (colin-king)]

I'll make it so that it will automatically scale back the number of AIO requests depending on the number of stressors and number of AIO requests available.

[Colin Ian King (colin-king)]

Fix committed: http://kernel.ubuntu.com/git/cking/stress-ng.git/commit/?id=e8af787982e85433cf858e1fc040e9e5683838cc

I'll try and get a new release out by EOW.

[Colin Ian King (colin-king)]

Fix releases, stress-ng V0.08.16