From jamie.levy at gmail.com Fri Aug 1 23:37:53 2008 From: jamie.levy at gmail.com (Jamie Levy) Date: Fri, 1 Aug 2008 19:37:53 -0400 Subject: [Fedora Women] question about /proc/kcore Message-ID: Hello, I know this list has been rather quiet for a while... so I might as well ask a question :-) I've been trying to find some information on /proc/kcore and have not been entirely successful. I know is that it is an alias to memory, that is in ELF format, and that can be used with gdb to debug the kernel. The `k' seems to imply that it is the kernel's memory, but all documentation I've found states that it is the size of physical memory plus 4KB (example below): https://www.redhat.com/docs/manuals/enterprise/RHEL-4-Manual/en-US/Reference_Guide/s2-proc-kcore.html This does not seem to be the case, however, when I do a listing in /proc/kcore on my machine (F8) which has 2 GB of memory: ls -lh /proc/kcore -r-------- 1 root root 897M 2008-08-01 19:05 /proc/kcore I have confirmed the same type of results on other machines to which I have access. I also do not seem to have the kcore.h file on my system (and I have kernel-devel installed), since it is a zero byte file: -rw-r--r-- 1 root root 0 2008-07-21 02:05 /usr/src/kernels/2.6.25.11-60.fc8-i686/include/config/proc/kcore.h I am also aware of other tools that can be used to extract information about kcore like the redhat crash utility: http://people.redhat.com/anderson/ I am wondering why there is a discrepancy between the documentation and the actual implementation of the /proc/kcore file? I would also like to know where I can find more detailed information about the kcore file besides the usual description of what it is and how to use it for debugging. All the best, -Jamie Levy From astarta at rat.ru Sat Aug 2 20:54:19 2008 From: astarta at rat.ru (Astarta) Date: Sun, 03 Aug 2008 00:54:19 +0400 Subject: [Fedora Women] question about /proc/kcore In-Reply-To: References: Message-ID: <4894C97B.8090305@rat.ru> Jamie Levy wrote: > Hello, > > I know this list has been rather quiet for a while... so I might as > well ask a question :-) Hello, I really thought that this list is completely dead :-) > > This does not seem to be the case, however, when I do a listing in > /proc/kcore on my machine (F8) which has 2 GB of memory: > > ls -lh /proc/kcore > -r-------- 1 root root 897M 2008-08-01 19:05 /proc/kcore > > I have confirmed the same type of results on other machines to which I > have access. I also do not seem to have the kcore.h file on my system > (and I have kernel-devel installed), since it is a zero byte file: > > -rw-r--r-- 1 root root 0 2008-07-21 02:05 > /usr/src/kernels/2.6.25.11-60.fc8-i686/include/config/proc/kcore.h > As far as I know, the size of kcore is equal not to the size of _all_ physical memory installed on the machine, but just to the amount of memory accessible by kernel. Your kernel seems to be compiled with HIGHMEM support, and if you do `ls -l /proc/kcore` you see your LOWMEM size, the real memory that the kernel uses. That the reason why the difference you mentioned comes. Someone will correct me, if I'm wrong :) > > All the best, > > -Jamie Levy > > _______________________________________________ > Fedora-women-list mailing list > Fedora-women-list at redhat.com > https://www.redhat.com/mailman/listinfo/fedora-women-list -- with best regards, Fadeeva Marina. From gayathri.swa at gmail.com Sat Aug 2 21:58:39 2008 From: gayathri.swa at gmail.com (Gayathri Swaminathan) Date: Sat, 2 Aug 2008 16:58:39 -0500 Subject: [Fedora Women] question about /proc/kcore In-Reply-To: <4894C97B.8090305@rat.ru> References: <4894C97B.8090305@rat.ru> Message-ID: Think Jamie is right. I have observed behaviour were this file grows based on accessed memory (would this be kernel shared mem params?) But it is definitely not just size of physical RAM+4KB on a machine. gayathri On Sat, Aug 2, 2008 at 3:54 PM, Astarta wrote: > Jamie Levy wrote: > >> Hello, >> >> I know this list has been rather quiet for a while... so I might as >> well ask a question :-) >> > > Hello, > > I really thought that this list is completely dead :-) > > >> This does not seem to be the case, however, when I do a listing in >> /proc/kcore on my machine (F8) which has 2 GB of memory: >> >> ls -lh /proc/kcore >> -r-------- 1 root root 897M 2008-08-01 19:05 /proc/kcore >> >> I have confirmed the same type of results on other machines to which I >> have access. I also do not seem to have the kcore.h file on my system >> (and I have kernel-devel installed), since it is a zero byte file: >> >> -rw-r--r-- 1 root root 0 2008-07-21 02:05 >> /usr/src/kernels/2.6.25.11-60.fc8-i686/include/config/proc/kcore.h >> >> > > As far as I know, the size of kcore is equal not to the size of _all_ > physical memory installed on the machine, but just to the amount of memory > accessible by kernel. > Your kernel seems to be compiled with HIGHMEM support, and if you do `ls -l > /proc/kcore` you see your LOWMEM size, the real memory that the kernel uses. > That the reason why the difference you mentioned comes. > > Someone will correct me, if I'm wrong :) > > >> All the best, >> >> -Jamie Levy >> >> _______________________________________________ >> Fedora-women-list mailing list >> Fedora-women-list at redhat.com >> https://www.redhat.com/mailman/listinfo/fedora-women-list >> > > > -- > with best regards, > Fadeeva Marina. > > > _______________________________________________ > Fedora-women-list mailing list > Fedora-women-list at redhat.com > https://www.redhat.com/mailman/listinfo/fedora-women-list > -- Gayathri Swaminathan gpgkey: 3EFB3D39 Volunteer, FDP -------------- next part -------------- An HTML attachment was scrubbed... URL: From jamie.levy at gmail.com Mon Aug 4 02:31:13 2008 From: jamie.levy at gmail.com (Jamie Levy) Date: Sun, 3 Aug 2008 22:31:13 -0400 Subject: [Fedora Women] question about /proc/kcore In-Reply-To: References: <4894C97B.8090305@rat.ru> Message-ID: Thank you both for your responses. I still have not figured this out, but I appreciate your replies. I wasn't sure if this list was still around, but I thought I would try to liven it up with a question ;-) All the best, -Jamie On Sat, Aug 2, 2008 at 5:58 PM, Gayathri Swaminathan wrote: > Think Jamie is right. > > I have observed behaviour were this file grows based on accessed memory > (would this be kernel shared mem params?) > > But it is definitely not just size of physical RAM+4KB on a machine. > > gayathri > > On Sat, Aug 2, 2008 at 3:54 PM, Astarta wrote: >> >> Jamie Levy wrote: >>> >>> Hello, >>> >>> I know this list has been rather quiet for a while... so I might as >>> well ask a question :-) >> >> Hello, >> >> I really thought that this list is completely dead :-) >> >>> >>> This does not seem to be the case, however, when I do a listing in >>> /proc/kcore on my machine (F8) which has 2 GB of memory: >>> >>> ls -lh /proc/kcore >>> -r-------- 1 root root 897M 2008-08-01 19:05 /proc/kcore >>> >>> I have confirmed the same type of results on other machines to which I >>> have access. I also do not seem to have the kcore.h file on my system >>> (and I have kernel-devel installed), since it is a zero byte file: >>> >>> -rw-r--r-- 1 root root 0 2008-07-21 02:05 >>> /usr/src/kernels/2.6.25.11-60.fc8-i686/include/config/proc/kcore.h >>> >> >> >> As far as I know, the size of kcore is equal not to the size of _all_ >> physical memory installed on the machine, but just to the amount of memory >> accessible by kernel. >> Your kernel seems to be compiled with HIGHMEM support, and if you do `ls >> -l /proc/kcore` you see your LOWMEM size, the real memory that the kernel >> uses. That the reason why the difference you mentioned comes. >> >> Someone will correct me, if I'm wrong :) >> >>> >>> All the best, >>> >>> -Jamie Levy >>> >>> _______________________________________________ >>> Fedora-women-list mailing list >>> Fedora-women-list at redhat.com >>> https://www.redhat.com/mailman/listinfo/fedora-women-list >> >> >> -- >> with best regards, >> Fadeeva Marina. >> >> _______________________________________________ >> Fedora-women-list mailing list >> Fedora-women-list at redhat.com >> https://www.redhat.com/mailman/listinfo/fedora-women-list > > > > -- > Gayathri Swaminathan > gpgkey: 3EFB3D39 > Volunteer, FDP > -- ============================== Jamie Levy Computer Science Dept Queens College http://venus.cs.qc.edu/~jlevy ============================== From gayathri.swa at gmail.com Mon Aug 4 12:39:28 2008 From: gayathri.swa at gmail.com (Gayathri Swaminathan) Date: Mon, 4 Aug 2008 07:39:28 -0500 Subject: [Fedora Women] question about /proc/kcore In-Reply-To: References: <4894C97B.8090305@rat.ru> Message-ID: And, thanks for bringing it to life! There are many RHEL-ish issues/resolutions that I encounter as well. Will start sharing them here on :) On Sun, Aug 3, 2008 at 9:31 PM, Jamie Levy wrote: > Thank you both for your responses. I still have not figured this out, > but I appreciate your replies. I wasn't sure if this list was still > around, but I thought I would try to liven it up with a question ;-) > > All the best, > > -Jamie > -------------- next part -------------- An HTML attachment was scrubbed... URL: