Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-05 Thread David Hildenbrand
On 04.06.20 22:00, Dave Hansen wrote: > On 6/4/20 11:12 AM, Daniel Jordan wrote: >>> E.g., on powerpc that's 16MB so they have *a lot* of memory blocks. >>> That's why that's not papering over the problem. Increasing the memory >>> block size isn't always the answer. >> Ok. If you don't mind, what

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread Daniel Jordan
On Thu, Jun 04, 2020 at 01:00:55PM -0700, Dave Hansen wrote: > On 6/4/20 11:12 AM, Daniel Jordan wrote: > >> E.g., on powerpc that's 16MB so they have *a lot* of memory blocks. > >> That's why that's not papering over the problem. Increasing the memory > >> block size isn't always the answer. > > O

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread Daniel Jordan
On Thu, Jun 04, 2020 at 08:55:19PM +0200, David Hildenbrand wrote: > >> E.g., on powerpc that's 16MB so they have *a lot* of memory blocks. > >> That's why that's not papering over the problem. Increasing the memory > >> block size isn't always the answer. > > > > Ok. If you don't mind, what's th

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread Dave Hansen
On 6/4/20 11:12 AM, Daniel Jordan wrote: >> E.g., on powerpc that's 16MB so they have *a lot* of memory blocks. >> That's why that's not papering over the problem. Increasing the memory >> block size isn't always the answer. > Ok. If you don't mind, what's the purpose of hotplugging at that granul

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread David Hildenbrand
>> E.g., on powerpc that's 16MB so they have *a lot* of memory blocks. >> That's why that's not papering over the problem. Increasing the memory >> block size isn't always the answer. > > Ok. If you don't mind, what's the purpose of hotplugging at that granularity? > I'm simply curious. On bare

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread Daniel Jordan
On Thu, Jun 04, 2020 at 07:45:40PM +0200, David Hildenbrand wrote: > On 04.06.20 19:22, Daniel Jordan wrote: > > IMHO the root cause of this is really the small block size. Building a > > cache > > on top to avoid iterating over tons of small blocks seems like papering over > > the problem, espec

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread David Hildenbrand
On 04.06.20 19:22, Daniel Jordan wrote: > On Thu, Jun 04, 2020 at 09:22:03AM +0200, David Hildenbrand wrote: >> On 04.06.20 05:54, Daniel Jordan wrote: >>> Some of our servers spend 14 out of the 21 seconds of kernel boot >>> initializing memory block sysfs directories and then creating symlinks >>

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread Daniel Jordan
On Thu, Jun 04, 2020 at 09:22:03AM +0200, David Hildenbrand wrote: > On 04.06.20 05:54, Daniel Jordan wrote: > > Some of our servers spend 14 out of the 21 seconds of kernel boot > > initializing memory block sysfs directories and then creating symlinks > > between them and the corresponding nodes.

Re: [PATCH] x86/mm: use max memory block size with unaligned memory end

2020-06-04 Thread David Hildenbrand
On 04.06.20 05:54, Daniel Jordan wrote: > Some of our servers spend 14 out of the 21 seconds of kernel boot > initializing memory block sysfs directories and then creating symlinks > between them and the corresponding nodes. The slowness happens because > the machines get stuck with the smallest s