On 2016/08/18 at 09:50, Zhou Wenjian wrote: > 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 at cn.fujitsu.com> > Acked-by: Baoquan He <bhe at redhat.com> > --- > Documentation/kdump/kdump.txt | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/Documentation/kdump/kdump.txt b/Documentation/kdump/kdump.txt > index 96da2b7..c93a6e0 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 should replace it by 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 > + a SMP dump-capture kernel and specify maxcpus\nr_cpus, disable_cpu_apicid=[X] s/a SMP/an SMP/ For "maxcpus\nr_cpus", I think to use slash instead of backslash in Linux is better. Otherwise, looks good to me. Regards, Xunlei > + 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
