Installation guide

Saving Memory Dumps
HP-UX version 11.00.03 Administering Fault Tolerant Hardware 5-45
Multiply the number of pages listed in Total pages included in dump by the page
size (4 KB), and add 25% for a margin of safety to give you an estimate of how
much dump space to provide. For example, (6208 x 4KB) x 1.25 = approximately
30MB of space needed.
Configuring save_mcore
You can configure save_mcore through the /etc/rc.config.d/savecrash
file.
Both dump utilities, save_mcore and savecrash, share the configuration file
/etc/rc.config.d/savecrash. The save_mcore utility uses the following
parameters in /etc/rc.config.d/savecrash (and ignores all other
parameters, which are used solely by savecrash):
■ SAVECRASH_DIR—You can configure the path used to locate the dump file
directory from the command line (save_mcore dirname) or through the
COREDIR parameter in the config file.
■ CHUNK_SIZE—Both save_mcore and savecrash save dumps as a
directory full of files (called chunks) with an index used to find pieces, as
required. This allows file systems with limited file size to be used to save a
large dump (as large as 16GB). You can set the chunk size by specifying a value
for this parameter. You can also configure chunk size from the command line
(save_mcore -s chunksize).
■ COMPRESS—Selective save_mcore, like savecrash, also provides dump
compression. This feature is configured from the command line (-z or -Z), or
via the COMPRESS parameter in the config file.
Se the save_mcore(1M) man pages for more information.
Using save_mcore for Full and Selective Dumps
The save_mcore command uses the following syntax:
save_mcore [-vnzZNfh] [-D phmemdevice] [-d sysfile]
[-m minfree] [-s chunksize] [-p npages] [dirname]
Table 5-11 describes the save_mcore options and parameters.
NOTE
The save_mcore and savecrash commands have many options and
parameters in common that operate in the same manner. The only
options and parameters that are unique to save_mcore are -h and
-p npages.