From mboxrd@z Thu Jan 1 00:00:00 1970 From: jun.nie@linaro.org (Jun Nie) Date: Fri, 30 Jan 2015 10:57:24 +0800 Subject: CMA related memory questions In-Reply-To: References: Message-ID: <54CAF314.4070301@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 2015?01?30? 10:36, Jun Nie wrote: > Hi Marek & Arnd, > > Did you ever know issue that free CMA memory is high, but system is > hungry for memory and page cache is very low? I am enabling CMA in > Android on my board with 512MB memory and see FreeMem in /proc/meminfo > increase a lot with CMA comparing the reservation solution on boot. But > I find system is not borrowing memory from CMA pool when running 3dmark > (high webkit workload at start). Because the FreeMem size is high, but > cache size decreasing significantly to several MB during benchmark run, > I suppose system is trying to reclaim memory from pagecache for new > allocation. My question is that what API that page cache and webkit > related functionality are using to allocate memory. Maybe page cache > require memory that is not movable/reclaimable memory, where we may have > optimization to go thru dma_alloc_xxx to borrow CMA memory? I suppose > app level memory allocation shall be movable/reclaimable memory and can > borrow from CMA pool, but not sure whether the flag match the > movable/reclaimable memory and go thru the right path. > > Could you help share your experience/thoughts on this? Thanks! > > > B.R. > Jun Add more people.