Re: [RFC 0/2] Delay initializing of large sections of memory

[Mike Travis <travis@sgi.com>]

On 6/25/2013 11:38 AM, Yinghai Lu wrote:
> On Tue, Jun 25, 2013 at 10:35 AM, Mike Travis <travis@sgi.com> wrote:
>>
>>
>> On 6/21/2013 5:23 PM, Yinghai Lu wrote:
>>> On Fri, Jun 21, 2013 at 2:30 PM, Mike Travis <travis@sgi.com> wrote:
>>>> Exactly.  That's why I left both low and high memory on each node.
>>>
>>> looks like you assume every node have same ram, and before booting you
>>> you need to know memory layout to append the boot command line.
>>>
>>> We have patchset that moving srat table parse early.
>>> git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-yinghai.git
>>> for-x86-mm
>>> https://git.kernel.org/cgit/linux/kernel/git/yinghai/linux-yinghai.git/log/?h=for-x86-mm
>>>
>>> on top that, we could make your patch pass more simple command like
>>> 1/2^n of every node, and only need to pass n instead.
>>
>> The two params that I couldn't figure out how to provide except via kernel
>> param option was the memory block size (128M or 2G) and the physical
>> address space per node.  The other 3 params can be automatically
>> setup by a script when the total system size is known.  As soon as we
>> verify on the 32TB system and surmise what will be needed for 64TB,
>> then those 3 params can probably disappear.
> 
> our "numa parsing early" patchset could provide "physical address
> space per node",
> also can calculate memory block size via alignment detection from numa info.

Thanks!  I'll try it out.
> 
> with that, user only can pass "delay_init_mem" only.
> 
> Thanks
> 
> Yinghai
>