Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: core dumps
Operating Systems Solaris core dumps Post 302318336 by pupp on Thursday 21st of May 2009 10:31:37 AM
Old 05-21-2009
core dumps
i had a situation where a process was defunct. preap would not reap the process and gcore would not work properly (not sure why). therefore, the suggestion was to force a panic and collect the core dump. obviously you could do a savecore -L and capture the dump without bringing down the system. However, I do realize that ram is still dynamic at that point and savecore does its best to capture the core at that time. half/reboot -d would give a much more accurate picture in the sense of time when savecore is ran.

my question is do you really see or can you see a big difference in the core dump doing say a reboot -d instead of savecore -L ?
 

10 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

reading core dumps

Does anyone know how to read core dumps. Is gdb the only tool for it ? The OS is Solaris. Thanks (2 Replies)
Discussion started by: suntan
2 Replies

2. Solaris

Generating core dumps

I have the following set up on a Sun server running solaris 5.8 for core dump generation coreadm global core file pattern: /var/core init core file pattern: /var/core global core dumps: enabled per-process core dumps: enabled global setid core dumps:... (4 Replies)
Discussion started by: handak9
4 Replies

3. Programming

strcmp core dumps

hi everyone, Right now when I do: strcmp(s1, s2); i get a core dump because at times s1 or s2 can be nothing so that makes strcmp() core dump. What is the solution, if at times I expect one of them (or both) to be NULL? I want to be able to compare that s1 is NULL and s2 is "blah" or... (6 Replies)
Discussion started by: annie
6 Replies

4. SCO

SCO 5.07 Panic / Core Dumps

Anyone know how you go about interrogating a panic / core dump with crash for SCO Unix (5 Replies)
Discussion started by: ccarcher
5 Replies

5. UNIX for Advanced & Expert Users

Using GDB to analyse different CORE dumps

Hi, Can we modify the GDB source code so as to analyze core dumps from different targets? From my analysis, I think we need to build our section table statically for each target. i.e., including the various address boundaries in build_section_table() function. If this is the case, then the GDB... (2 Replies)
Discussion started by: nsdeeps
2 Replies

6. Programming

AIX core dumps

My program is not dumping core when hitting a segmentation violation inside a thread. However, it dumps core when the segv occurs within main. Any ideas on how to diagnose this? AIX 5.3 (4 Replies)
Discussion started by: bean66
4 Replies

7. Ubuntu

enabling core dumps for daemon processes

Hello, I am debugging a program which works as daemon. It sigfaults, unfortunately I'm unable to generate core dump file. Here is what I am doing: tsurko@bastila:~$ ulimit -c unlimited tsurko@bastila:~$ ulimit -c unlimited tsurko@bastila:~$ cat /etc/sysctl.conf | grep 'core_pattern'... (1 Reply)
Discussion started by: tsurko
1 Replies

8. Red Hat

generating core dumps

Hi I have a Fedora installed and I try to generate my application's core dump file. My system has no coredump limit: $ ulimit core file size (blocks, -c) unlimited But when my application crashes no core dumps generated. I can generate dump file using gcore but it is not appropraite... (1 Reply)
Discussion started by: xyzt
1 Replies

9. Programming

Stack only core dumps

I'm working on a program in Linux with a group of people scattered around the country. When we have a crash, I like to send a core dump to the appropriate person so that they can understand the problem better. The problem is that our application uses several gigabytes worth of data and these... (4 Replies)
Discussion started by: bmsterner
4 Replies

10. HP-UX

Generate core dumps

kill -SEGV <pid> gives me the core file for that process but also terminates the process. Can I not get the core dump without terminating the process ? (2 Replies)
Discussion started by: mohtashims
2 Replies

LEARN ABOUT SUNOS

savecore

savecore(1M)						  System Administration Commands					      savecore(1M)

NAME

       savecore - save a crash dump of the operating system

SYNOPSIS

       /usr/bin/savecore [-Lvd] [-f dumpfile] [directory]

DESCRIPTION

       The  savecore  utility saves a crash dump of the kernel (assuming that one was made) and writes a reboot message in the shutdown log. It is
       invoked by the dumpadm service each time the system boots.

       savecore saves the crash dump data in the file directory/vmcore.n and the kernel's namelist in directory/unix.n. The  trailing  .n  in  the
       pathnames is replaced by a number which grows every time savecore is run in that directory.

       Before writing out a crash dump, savecore reads a number from the file directory/minfree. This is the minimum number of kilobytes that must
       remain free on the file system containing directory. If after saving the crash dump the file system containing directory  would	have  less
       free  space the number of kilobytes specified in minfree, the crash dump is not saved. if the minfree file does not exist, savecore assumes
       a minfree value of 1 megabyte.

       The savecore utility also logs a reboot message using facility LOG_AUTH (see syslog(3C)). If the system crashed as a  result  of  a  panic,
       savecore logs the panic string too.

OPTIONS

       The following options are supported:

       -d	       Disregard  dump	header valid flag. Force savecore to attempt to save a crash dump even if the header information stored on
		       the dump device indicates the dump has already been saved.

       -f dumpfile     Attempt to save a crash dump from the specified file instead of from the system's current dump device. This option  may	be
		       useful if the information stored on the dump device has been copied to an on-disk file by means of the dd(1M) command.

       -L	       Save  a	crash  dump of the live running Solaris system, without actually rebooting or altering the system in any way. This
		       option forces savecore to save a live snapshot of the system to the dump device, and then immediately to retrieve the  data
		       and  to	write it out to a new set of crash dump files in the specified directory. Live system crash dumps can only be per-
		       formed if you have configured your system to have a dedicated dump device using dumpadm(1M).

		       savecore -L does not suspend the system, so the contents of memory continue to change while the dump is saved.  This  means
		       that live crash dumps are not fully self-consistent.

       -v	       Verbose. Enables verbose error messages from savecore.

OPERANDS

       The following operands are supported:

       directory	       Save  the crash dump files to the specified directory. If directory is not specified, savecore saves the crash dump
			       files to the default savecore directory, configured by dumpadm(1M).

FILES

       directory/vmcore.n

       directory/unix.n

       directory/bounds

       directory/minfree

       /var/crash/'uname -n'	       default crash dump directory

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       adb(1), mdb(1), svcs(1), dd(1M), dumpadm(1M), svcadm(1M), syslog(3C), attributes(5), smf(5)

NOTES

       The system crash dump service is managed by the service management facility, smf(5), under the service identifier:

       svc:/system/dumpadm:default

       Administrative actions on this service, such as enabling, disabling, or requesting restart, can be performed  using  svcadm(1M).  The  ser-
       vice's status can be queried using the svcs(1) command.

       If the dump device is also being used as a swap device, you must run savecore very soon after booting, before the swap space containing the
       crash dump is overwritten by programs currently running.

SunOS 5.10							    25 Sep 2004 						      savecore(1M)
All times are GMT -4. The time now is 03:21 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy