From mboxrd@z Thu Jan 1 00:00:00 1970 From: Henrique Marks Date: Wed, 7 Nov 2018 16:07:32 -0200 (BRST) Subject: [Buildroot] Weird OOM problem In-Reply-To: References: Message-ID: <391130199.694669.1541614052863.JavaMail.zimbra@datacom.com.br> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Hi Patrick, ----- Mensagem original ----- > De: "Patrick Doyle" > Para: "buildroot" > Enviadas: Quarta-feira, 7 de novembro de 2018 13:07:54 > Assunto: [Buildroot] Weird OOM problem > Hello fellow buildrooters. > I know this is the wrong list on which to ask this question, but you > are all experts in this field and can probably either direct me to the > proper list, or give me some tips here. (After all, this is where I > hang out). > > I have an embedded system with 128MB of RAM and no SWAP. > > /tmp is mounted on a tmpfs > > Shortly after boot, I can log in and look at how much memory is free: > > # free > total used free shared buffers cached > Mem: 120912 45224 75688 100 7700 17900 > -/+ buffers/cache: 19624 101288 > Swap: 0 0 0 > > I create a 25MB file in /tmp, and look again: > # dd if=/dev/urandom bs=1M count=25 of=/tmp/foo > 25+0 records in > 25+0 records out > # free > total used free shared buffers cached > Mem: 120912 53620 67292 25700 1040 33324 > -/+ buffers/cache: 19256 101656 > Swap: 0 0 0 > > If I try to create a 2nd 25MB file (or even an 8MB file) in /tmp, then > the OOM killer kicks in, despite the cat that I have somewhere between > 67 and 101MB free. > > It would appear that the OOM killer kicks in when the disk cache (aka > "shared") grows beyond 25% of total RAM. > > Is that true? Can I tune that? > > I am going to keep looking on my own now that I have learned this > much, but I figured I would put the question out to the experts in the > mean time. > > Thanks for any tips you can give me, (even if the tip is, "Go ask SO"). > > --wpd > _______________________________________________ > buildroot mailing list > buildroot at busybox.net > http://lists.busybox.net/mailman/listinfo/buildroot Had some problems with this, it was caused by the use of a RAMDISK and a wrong parameter passed by uboot for the kernel. Can you post the line you use ? Thanks -- Dr. Henrique Marks henrique.marks at datacom.ind.br R. Am?rica, 1000 - Eldorado do Sul - RS CEP: 92990-000 - Brasil Fone: +55 51 3933 3000 - Ramal 3466