Hello David, Am Freitag, 18. September 2020, 09:44:10 CEST schrieb David Bauer: > Hello Sven, > > On 9/18/20 1:27 AM, Sven Roederer wrote: > > Adrian, David, > > > > Am Mittwoch, 16. September 2020, 16:15:42 CEST schrieb David Bauer: > >> Hi, > >> > >> On 9/16/20 11:40 AM, Adrian Schmutzler wrote: > >>>> -----Original Message----- > >>>> From: openwrt-devel [mailto:openwrt-devel-boun...@lists.openwrt.org] > >>>> On Behalf Of Sven Roederer > >>>> Sent: Mittwoch, 16. September 2020 09:17 > >>>> To: openwrt-devel@lists.openwrt.org > >>>> Subject: ath79: move 8/32 boards to tiny subtarget > >>>> > >>>> Hi, > >>>> > >>>> not sure if this has been discussed before. > >>>> I recently worked with some 8/32 boards (Ubiquiti Nanostation M (XM), > >>>> TPLink > >>>> WR842 v2) for our Freifunk-project and realized that the low RAM > >>>> situation > >>>> requires quite different handling than the full boards (8+/64+). > >>>> > >>>> I wonder if there is a reason to not move the boards, which are > >>>> affected > >>>> by > >>>> the 4/32MB warning also, to the ath79-tiny target? > >>> > >>> I wonder whether the tiny subtarget will actually make much difference > >>> for > >>> RAM issues? > > > > My idea based on the fact, to have an easy way to disable certain kernel- > > features to reduce teh kernel-size (in flash and RAM). Candidates I see > > here are: USB-Support, additional filesystems, block-devices, ... > > Even some devices provide USB-connectors it might be better to have less > > OOM- crashes and reboots than installing a usb-flashdrive. In our > > Freifunk-Firmware I've seen much less runtime-problems with a stripped > > down kernel. > > With having the 8/32 in tiny it would just be a config-file for the > > low-RAM > > boards. Having them in generic subtarget would require to build 2 kernels > > for the same subtarget. > > > >> In it's current state, it will most likely increase low-memory issues as > >> the squashfs blocksize is 1024kB compared to the regular 256kB. Not that > >> ath79-tiny has no target-flag for small memory set. > > > > Did you miss an "e" ? "Note that ath79-tiny has ..." gives more sense to > > me. Reading it this way, you expect the larger blocksize was choosen as > > tradeoff between using the flash most efficient vs. RAM for the 4/32 > > boards? I've seen there is a low_mem flag for some 16MB boards defined. > > It seems that for some config-options SMALL_FLASH and LOW-MEM are > > conflicting. > > Yes, there was an e missing. > > We've experienced severe system instabilities with larger blocksizes (the > default one for ar71xx-tiny to be precise) downstream. [0] [1] > > However, In my opinion the blocksize upstream works well for people looking > for a home router, as memory consumption is typically lower and some > additional space is desirable there. >
For that reason Freifunk-Gluon and Freifunk-Berlin use the non-default value. Esp. for the routing-daemons these project need more RAM for apps running. > I could also imagine the low-mem target feature and It's configuration > implications have to be assessed as a whole, given it did not experience > much use for a longer period of time. > Indeed "LOW_MEMORY_FOOTPRINT" seems only to affedt 3 general options and one option of OpenSSL. So it might be an option to : * set LOW_MEM for 8/32 MB devies * set LOW_MEM and SMALL_FLASH for 4/32 MB devices * check the CONFIG-options for usefull defaults So the tiny aubtarget can be defined as "boards with 32MB or less of RAM; some boards also with only 4MB of flash". This definition would essentially match the "4/32 warning" [1]. [1] - https://openwrt.org/supported_devices/432_warning Sven > [0] https://github.com/freifunk-gluon/gluon/issues/2032 > [1] > https://github.com/freifunk-gluon/gluon/commit/7e8af99cf504ca1dc389f282a0c9 > 4f4a911571be > _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel