NAME
gcore - gcore - retrieve a process image as a core dump
SYNOPSIS
gcore
gcore [-v vlevel] [-f filter] [pid | taskp]*
This command retrieves a process image as a core dump.
DESCRIPTION
-v Display verbose information according to vlevel:
progress library error page fault
---------------------------------------
0
1 x
2 x
4 x (default)
7 x x x
-f Specify kinds of memory to be written into core dumps according to
the filter flag in bitwise:
AP AS FP FS ELF HP HS DD
----------------------------------
0
1 x
2 x
4 x
8 x
16 x x
32 x
64 x
128 x
255 x x x x x x x x
AP Anonymous Private Memory
AS Anonymous Shared Memory
FP File-Backed Private Memory
FS File-Backed Shared Memory
ELF ELF header pages in file-backed private memory areas
HP Hugetlb Private Memory
HS Hugetlb Shared Memory
DD Memory advised using madvise with MADV_DONTDUMP flag
-V Display version information
If no pid or taskp is specified, gcore tries to retrieve the process image
of the current task context.
The file name of a generated core dump is core.<pid> where pid is PID of
the specified process.
For a multi-thread process, gcore generates a core dump containing
information for all threads, which is similar to a behaviour of the ELF
core dumper in Linux kernel.
Notice the difference of PID on between crash and linux that ps command in
crash utility displays LWP, while ps command in Linux thread group tid,
precisely PID of the thread group leader.
gcore provides core dump filtering facility to allow users to select what
kinds of memory maps to be included in the resulting core dump. There are
7 kinds memory maps in total, and you can set it up with set command.
For more detailed information, please see a help command message.
EXAMPLES
Specify the process you want to retrieve as a core dump. Here assume the
process with PID 12345.
crash> gcore 12345
Saved core.12345
crash>
Next, specify by TASK. Here assume the process placing at the address
f9d7000 with PID 32323.
crash> gcore f9d78000
Saved core.32323
crash>
If multiple arguments are given, gcore performs dumping process in the
order the arguments are given.
crash> gcore 5217 ffff880136d72040 23299 24459 ffff880136420040
Saved core.5217
Saved core.1130
Saved core.1130
Saved core.24459
Saved core.30102
crash>
If no argument is given, gcore tries to retrieve the process of the current
task context.
crash> set
PID: 54321
COMMAND: "bash"
TASK: e0000040f80c0000
CPU: 0
STATE: TASK_INTERRUPTIBLE
crash> gcore
Saved core.54321
When a multi-thread process is specified, the generated core file name has
the thread leader's PID; here it is assumed to be 12340.
crash> gcore 12345
Saved core.12340
It is not allowed to specify two same options at the same time.
crash> gcore -v 1 1234 -v 1
Usage: gcore
gcore [-v vlevel] [-f filter] [pid | taskp]*
gcore -d
Enter "help gcore" for details.
It is allowed to specify -v and -f options in a different order.
crash> gcore -v 2 5201 -f 21 ffff880126ff9520 5205
Saved core.5174
Saved core.5217
Saved core.5167
crash> gcore 5201 ffff880126ff9520 -f 21 5205 -v 2
Saved core.5174
Saved core.5217
Saved core.5167