On Fri, 2022-06-03 at 08:49 +0200, Joakim Tjernlund wrote: > On Thu, 2022-06-02 at 21:11 +0100, Matthew Wilcox wrote: > > On Thu, Jun 02, 2022 at 07:24:23PM +0000, Joakim Tjernlund wrote: > > > We have this small embedded target(aarch64) with 32 MB of RAM where the kernel consumes 14420K: > > > Memory: 22444K/36864K available (3584K kernel code, 698K rwdata, 936K rodata, 320K init, 255K bss, 14420K reserved, 0K cma-reserved) > > > > > > I want to track down were most of this RAM is consumed so I can trim away some MBs > > > but I am having a hard time finding may way. > > > Is there some tool/kernel config that can help me with that? > > > > You may find this series of articles interesting: > > > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flwn.net%2FArticles%2F741494%2F&data=05%7C01%7CJoakim.Tjernlund%40infinera.com%7C509eaa2f688b4612945208da44d40494%7C285643de5f5b4b03a1530ae2dc8aaf77%7C1%7C0%7C637897974658412129%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=zP2oazSeoVKiTrbPONqmQXEhzyIIL3pQdvsKfN8nOA0%3D&reserved=0 > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flwn.net%2FArticles%2F744507%2F&data=05%7C01%7CJoakim.Tjernlund%40infinera.com%7C509eaa2f688b4612945208da44d40494%7C285643de5f5b4b03a1530ae2dc8aaf77%7C1%7C0%7C637897974658412129%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=9kNmXDhuQ24tWlECGrYQOqaaTsc0sOO4TozcQBk5aYc%3D&reserved=0 > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flwn.net%2FArticles%2F746780%2F&data=05%7C01%7CJoakim.Tjernlund%40infinera.com%7C509eaa2f688b4612945208da44d40494%7C285643de5f5b4b03a1530ae2dc8aaf77%7C1%7C0%7C637897974658412129%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=ZFu0q4tXX677JwkgBqK73M8WxDrhylw0XnuEw5Y8mA4%3D&reserved=0 > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flwn.net%2FArticles%2F748198%2F&data=05%7C01%7CJoakim.Tjernlund%40infinera.com%7C509eaa2f688b4612945208da44d40494%7C285643de5f5b4b03a1530ae2dc8aaf77%7C1%7C0%7C637897974658412129%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=ws5Rlrhts80ndzr8aEv3xTu6EmCnND3L%2FmGXHLDaygw%3D&reserved=0 > > > > While they're a little old and they're targetting a much smaller system > > than yours, they may give you some ideas of things you can try and tools > > you can use. > > Those are interesting, thanks. > In my case it is the amount of work space RAM allocated that is a bit much. The kernel code/data > is 5+MB but the total need is 14MB, 9MB is buffer and similar. > > Jocke Found something, arm64 only supports mem model SPARSEMEM_EXTREME and it uses most of my memory. Tried to force SPARSEMEM_STATIC but that didn't boot, is STATIC even cheaper ?
