Installation guide

Table 5-11. save_mcore Options and Parameter
Option Description
-v Enables additional progress messages and diagnostics.
-n Skip saving kernel modules.
-z Compress all physical memory image files and kernel module
files in the dump directory.
-Z Do not compress any files in the dump directory.
-f Generate a byte-for-byte full dump. All of memory is written to
one output file. In this mode, dirname/crash.n is the actual
output file instead of a directory. No compression is applied to the
file, and the -n and -s options, if specified, have no effect.
By default, save_mcore provides a selective dumping scheme.
Physical pages are filtered based on a specified dump criteria and
only the designated sorts of pages are saved into the dump. This
reduces the time required to take a dump as well as the overall
size of the dump file(s). This feature can be disabled from the
command line (-f).
-h Display a simple usage explanation on stderr.
-D phmemdev Harvest the dump from phmemdev, the device containing the
offline memory (from which the dump is to be harvested). If you
omit his option, save_mcore automatically selects the appropriate
device.
-d sysfile sysfile is the name of a file containing the image of the kernel
that produced the core dump (that is, the system running when
the crash occurred). If this option is not specified, save_mcore will
use /stand/vmunix. If the file containing the image of the
system that caused zero, and the default unit is kilobytes.
-m minfree Reserve additional space on the file system for other uses, where
minfree is the amount of additional space to reserve. This option
is useful for ensuring enough space is available.
-s chunksize Set the size of a single physical memory image file before
compression. The value must be a multiple of page size (divisible
by 4) and between 64 and 1048576. chunksize can be specified in
units of bytes (b), kilobytes (k), megabytes (m), or gigabytes (g).
Larger numbers increase compression efficiency at the expense of
both save_mcore time and debugging time.
-p npages Sleep one (1) second for each npages dumped. This setting is
used a boot time to limit the impact of a dump on the rest of the
system’s performance.