XRP Ninja

Update: the kernel patch is already in 2.6.34-rcN. Currently, in top, the SWAP column only shows the difference between VIRT and RES: case P_SWP: MKCOL(scale_num(PAGES_TO_KB(p->size - p->resident), w, s)); So currently the value is of no use. As a matter of fact, a recent enough kernel has provided the information which is needed to calculate the swap usage for each process. It is in /proc/$PID/smaps. But using smaps may affect top's performance because you have to calculate the sum yourself. But with this patch https://patchwork.kernel.org/patch/56929/ , the kernel will keep track of each process's swap usage for you. This patch (maybe not exactly in the same shape) is already in mmotm tree ( http://userweb.kernel.org/~akpm/mmotm/ ) 2.6.34-rcN. However, checking the /proc/$PID/status file directly may not be a thing which people would like to do. So I decided to make a patch for ps and top. Now it seems to be working. This is the vanilla ps: $ ps -o m_swap,comm...

If you are into investigating coredumps, or you are just curious about how many processes have coredumped, then this is for you: 1. add the following line to /etc/security/limits.conf * - core unlimited 2. add the following line to /etc/sysctl.conf kernel.core_pattern = /corefiles/core.%e.%p %e is the executable filename, %p is pid. Please check the "Naming of core dump files" section of man 5 core for more information on this. 3. run "sysctl -p", then logout and login. Or just reboot. This is what I have on my Yeeloong: $ ls /corefiles/ core.genstrings.11832 core.nscd.10278 core.nscd.12821 core.nscd.13617 core.nscd.23172 core.nscd.29367 core.nscd.6428 core.genstrings.18210 core.nscd.10281 core.nscd.13061 core.nscd.13620 core.nscd.23175 core.nscd.29368 core.nscd.6431 core.main.19478 core.nscd.10284 core.nscd.13064 core.nscd.19028 core.nscd.24042 core.nscd.29369 core.main.19702 core.nsc...

One of my friends has been to Antarctica. She has taken some photos of Gentoo Penguin. Enjoy! (and sorry the blog is in Chinese. :P) http://blog.sina.com.cn/s/blog_657eb8a70100h34p.html

Anyone in Nuremberg? ;) Activity : Linux Kernel Internals and Crash Dump Analysis Activity Code : Linux-IHC-001 Type : Internally Held Classroom From : 01/26/2010 To : 01/28/2010 Facility: EMEA - Nuernberg, DEU

I got a laptop from my employer (Novell) nearly 3 months ago. I installed both Gentoo and SLED in it. I didn't setup fbsplash on it when I installed Gentoo. I tried it today. However, I found the progress bar in silent mode did not progress. It stayed at "Initializing kernel", 0%. Finally, I found the reason was that I didn't have "/lib/rc/plugins" directory and as a consequence splashutils openrc plugin splash.so can't be installed into this directory. And that's why the progress bar does not progress. I think maybe it is a bug in openrc. But I am not sure and I can't investigate it further today, it is already 3 pm. :( So I just left a note here. :)

1. git clone git://www.gentoo-cn.org/var/git/loongson.git 2. Don't include loongson overlay's directory directly in your PORTDIR_OVERLAY. But in your own overlay, like /usr/local/portage, create symlinks pointing to sys-devel/ and sys-libs/glibc in loongson overlay. This is because you may not want to install packages from loongson overlay in your host machine. Also you need to make sure your own overlay is the first overlay containing binutils/gcc/glibc in your PORTDIR_OVERLAYS list. You may check the value of this list using command: portageq envvar PORTDIR_OVERLAY 3. Then, just run crossdev -t mips64el-unknown-linux-gnu. This command installed the following components on my host machine: linux-headers-2.6.27-r2 from portage. binutils-2.19.1-r1 from loongson overlay. gcc-4.4.2 from portage. The gcc in loongson overlay currently is just a symlink to portage gcc. glibc-2.9_p2009042 from loongson overlay. However if you build the toolchain now, glibc-2.10.1 will be installed ins...

Update: as reported by Fai Wong, -O1 is actually fine. Obviously, it must be some flag(s) which is(are) enabled at -O2 but not at -O1 caused this problem. However, it is not a priority ATM. Anyone who is interested in it is welcome to investigate it further. As I have mentioned earlier , sqlite compiled with -O2 may cause xulrunner to segfault in N32 userland on Loongson. Well, I almost forget it. So to remove the -O2 from CFLAGS once and for all, I adopted the technique described here . zhangle@2f env $ pwd /etc/portage/env zhangle@2f env $ find . ./dev-db ./dev-db/sqlite ./O2-removal zhangle@2f env $ cat O2-removal pre_pkg_setup() { elog "bashrc is removing \"-O2\" from CFLAGS for $PN" CFLAGS="${CFLAGS/-O2/}" } zhangle@2f env $ ls -l dev-db/sqlite lrwxrwxrwx 1 zhangle zhangle 13 2009-08-01 16:10 dev-db/sqlite -> ../O2-removal