peterz@infradead.org writes:

But then how can it run-away like Waiman suggested?

Probably because he's not running with that commit at all. We and others use 
this to prevent runaway allocation on a huge range of production and desktop 
use cases and it works just fine.

/me goes look... and finds MEMCG_MAX_HIGH_DELAY_JIFFIES.

That's a fail... :-(

I'd ask that you understand a bit more about the tradeoffs and intentions of 
the patch before rushing in to declare its failure, considering it works just 
fine :-)

Clamping the maximal time allows the application to take some action to 
remediate the situation, while still being slowed down significantly. 2 seconds 
per allocation batch is still absolutely plenty for any use case I've come 
across. If you have evidence it isn't, then present that instead of vague 
notions of "wrongness".