Hello,
Thanks for reviewing. I will resend the v2 patch.
On 09/16/2015 02:20 PM, Pratyush Anand wrote:
Hi Zhou,
Thanks for your work.
It seems its a V2. So please prefix with PATCH V2 and resend.
You can use:
git format-patch --subject-prefix="PATCH V2"
I see.
On 15/09/2015:10:34:14 AM, Zhou Wenjian wrote:
> Add descriptions of parallel dumping and how to use it.
>
> Signed-off-by: Zhou Wenjian <zhouwj-fnst(a)cn.fujitsu.com>
> ---
And since its a single patch so, after you have done format-patch, please write
a change log here as it has been written in
https://lists.fedoraproject.org/pipermail/kexec/2015-August/002271.html
I see.
> kexec-kdump-howto.txt | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/kexec-kdump-howto.txt b/kexec-kdump-howto.txt
> index 05b497f..97a319c 100644
> --- a/kexec-kdump-howto.txt
> +++ b/kexec-kdump-howto.txt
> @@ -616,6 +616,38 @@ options are copied from /proc/cmdline. In general it is best to
append
> command line options using "KDUMP_COMMANDLINE_APPEND=" instead of
replacing
> the original command line completely.
>
> +Parallel Dumping Operation
> +==========================
> +Kexec allows kdump using multiple cpus. So parallel feature can accelerate
> +dumping substantially, especially in executing compress and filter.
> +For example:
> +
> + 1."makedumpfile -c --num-threads [THREAD_NUM] /proc/vmcore dumpfile"
> + 2."makedumpfile -c /proc/vmcore dumpfile",
> +
> + 1 has better performance than 2, if THREAD_NUM is larger than two
> + and the usable cpus number is larger than THREAD_NUM.
> +
> +Notes on how to use multiple cpus on a capture kernel on x86 system:
> +
> +Make sure that you are using a sufficiently new kernel version that supports
I remember Dave suggested to avoid "sufficiently new". So, if you do not agree
with some comment then please let that know, otherwise reviewer will assume that
you agreed.
Sorry, I haven't noticed that.
> +disable_cpu_apicid kernel option as a capture kernel, which is
needed to
> +avoid x86 specific hardware issue (*). The disable_cpu_apicid kernel option
> +is automatically appended by kdumpctl script and is ignored if the kernel
> +doesn't support it.
> +
> +You need to specify how many cpus to be used in a capture kernel by specifying
> +the number of cpus in nr_cpus kernel option in /etc/sysconfig/kdump. nr_cpus
> +is 1 at default.
> +
> +You should use necessary and suffcient amount of cpus on a capture kernel.
I still think that "number of cpus" would have been a better choice than
"amount
of cpus".
I see.
--
Thanks
Zhou
Other than above two minor thing, patch looks fine to me.
~Pratyush