diff options
| author | Zhou Wenjian <zhouwj-fnst@cn.fujitsu.com> | 2016-09-19 13:59:49 +0800 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2016-09-20 18:02:54 -0600 |
| commit | ebf137f6703bc2cb055f4c000adc99e6ece4485d (patch) | |
| tree | 035e0af490a062d7e8b18b5d16b1abe3cb1c46cd /Documentation/kdump | |
| parent | 3dfb4c1bf049535c82843fc4f9c37b635fe6494e (diff) | |
Documentation: kdump: Add description of enable multi-cpus support
Multi-cpu support is useful to improve the performance of kdump in
some cases. So add the description of enable multi-cpu support in
dump-capture kernel.
Signed-off-by: Zhou Wenjian <zhouwj-fnst@cn.fujitsu.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Xunlei Pang <xpang@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/kdump')
| -rw-r--r-- | Documentation/kdump/kdump.txt | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/kdump/kdump.txt b/Documentation/kdump/kdump.txt index f7ef34065d54..b0eb27b956d9 100644 --- a/Documentation/kdump/kdump.txt +++ b/Documentation/kdump/kdump.txt @@ -396,6 +396,13 @@ Notes on loading the dump-capture kernel: Note, though maxcpus always works, you had better replace it with nr_cpus to save memory if supported by the current ARCH, such as x86. +* You should enable multi-cpu support in dump-capture kernel if you intend + to use multi-thread programs with it, such as parallel dump feature of + makedumpfile. Otherwise, the multi-thread program may have a great + performance degradation. To enable multi-cpu support, you should bring up an + SMP dump-capture kernel and specify maxcpus/nr_cpus, disable_cpu_apicid=[X] + options while loading it. + * For s390x there are two kdump modes: If a ELF header is specified with the elfcorehdr= kernel parameter, it is used by the kdump kernel as it is done on all other architectures. If no elfcorehdr= kernel parameter is |