On Tue, Jan 31, 2023 at 12:10:01PM -0800, Sukadev Bhattiprolu wrote: > On Tue, Jan 31, 2023 at 10:10:40AM -0800, Roman Gushchin wrote: > > Hi Sukadev! > > > > Can you, please, share a bit more details about your setup? E.g. what is > > the zone size, the cma area size and the value you want to set your sysctl to? > > Hi Roman, > > I currently have a device with 8GB Zone normal and 600MB of CMA. We have a > slightly different implementation and use up all the available CMA region. > i.e. going forward, we intend to set the ratio to 100 or even higher. It means you want allocations be always served from a cma region first? What's the point of it? The idea behind the current formula is to keep cma regions free if there is a plenty of other free memory, otherwise treat it on par with other memory. To justify a new sysctl you really need a solid use case, which is not limited to your custom implementation. Also, if decide to go with a new sysctl, we probably want to define it differently, e.g. as a [0-1000)/1000 of the zone size. But, honestly, I'm not sold yet. Thanks!
