From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH 0/6] Shrinking DT memory usage Date: Fri, 6 Oct 2017 17:10:22 -0500 Message-ID: References: <20171005194422.26224-1-robh@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Nicolas Pitre Cc: "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Frank Rowand , Grant Likely List-Id: devicetree@vger.kernel.org On Fri, Oct 6, 2017 at 4:30 PM, Nicolas Pitre wrote: > On Thu, 5 Oct 2017, Rob Herring wrote: > >> On kernels with a minimal config and a RAM target in the 100s of KB, DT >> is quite a hog of runtime memory usage. How much is dependent on how many >> nodes and properties in the DT which have a corresponding struct device_node >> and struct property in the kernel. Just skipping disabled nodes saves a >> lot by not creating the device_nodes in the first place[1], but there's >> more low hanging fruit by making some of the fields in struct property and >> struct device_node optional. With the changes here, the memory usage goes >> from 17KB to under 8KB on QEMU's ARM virt machine which is a relatively >> small DT. > > My test case went from 118072 bytes ddown to 21548 bytes with this > series. Did that include the changes for FDT skipping status=disabled and to stop storing the full path of every node? With those 2 alone you said it dropped to 25K. > Tested-by: Nicolas Pitre Thanks. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html