[Intel-gfx] [PATCH i-g-t] tests/gem_render_linear_blits: Increase min swap required

[Dave Gordon]

On 29/07/15 14:15, Chris Wilson wrote:
> On Wed, Jul 29, 2015 at 01:10:23PM +0000, Gore, Tim wrote:
>> I don’t see how this implies a kernel bug. It seems like a test problem (my
>> subtest as it happens). I was unaware of Android systems with small swap
>> partitions (or indeed any swap at all). Not sure I can understand the logic of
>> such a tiny swap partition but given the situation, unless we can accurately
>> characterise the memory usage of the test in advance then we have to
>> either skip the test for small swap, or try to monitor memory usage in an
>> ongoing way during the test.
>
> If the system has enough resources to run the test (that is enough
> physical to run an individual batch plus enough swap to hold the rest),
> then the test must not oom.
> -Chris

The test is deliberately attempting to use enough memory to force some 
stuff out to swap, while not hitting a total OOM. That can be a very 
narrow window when the swapspace is small; and the test just guesses in 
advance how much will do the trick rather than gradually increasing its 
demands until it detects that stuff is being swapped.

So not a kernel bug, but something of a failure in the implementation of 
the test. Is there an interface it could use to /detect and measure/ 
when stuff is swapped out?

.Dave.