Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-15 Thread Michal Hocko
On Tue 14-03-17 14:20:14, Igor Mammedov wrote: > On Mon, 13 Mar 2017 13:28:25 +0100 > Michal Hocko wrote: > > > On Mon 13-03-17 11:55:54, Igor Mammedov wrote: > > > On Thu, 9 Mar 2017 13:54:00 +0100 > > > Michal Hocko wrote: [...] > > > > The kernel is supposed to provide a proper API and that i

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-14 Thread Igor Mammedov
On Mon, 13 Mar 2017 13:28:25 +0100 Michal Hocko wrote: > On Mon 13-03-17 11:55:54, Igor Mammedov wrote: > > On Thu, 9 Mar 2017 13:54:00 +0100 > > Michal Hocko wrote: > > > > [...] > > > > It's major regression if you remove auto online in kernels that > > > > run on top of x86 kvm/vmware hype

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-13 Thread Vitaly Kuznetsov
Michal Hocko writes: > On Mon 13-03-17 14:42:37, Vitaly Kuznetsov wrote: >> > >> > What is the API those guests ask for the memory? And who is actually >> > responsible to ask for that memory? Is it a kernel or userspace >> > solution? >> >> Whatever, this can even be a system administrator runn

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-13 Thread Michal Hocko
On Mon 13-03-17 14:42:37, Vitaly Kuznetsov wrote: > Michal Hocko writes: > > > On Mon 13-03-17 13:54:59, Vitaly Kuznetsov wrote: > >> Michal Hocko writes: > >> > >> > On Mon 13-03-17 11:55:54, Igor Mammedov wrote: > >> >> > > > >> >> > >- suggested RFC is not acceptable from virt point

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-13 Thread Vitaly Kuznetsov
Michal Hocko writes: > On Mon 13-03-17 13:54:59, Vitaly Kuznetsov wrote: >> Michal Hocko writes: >> >> > On Mon 13-03-17 11:55:54, Igor Mammedov wrote: >> >> > > >> >> > >- suggested RFC is not acceptable from virt point of view >> >> > > as it regresses guests on top of x86 k

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-13 Thread Michal Hocko
On Mon 13-03-17 13:54:59, Vitaly Kuznetsov wrote: > Michal Hocko writes: > > > On Mon 13-03-17 11:55:54, Igor Mammedov wrote: > >> > > > >> > >- suggested RFC is not acceptable from virt point of view > >> > > as it regresses guests on top of x86 kvm/vmware which > >> > >

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-13 Thread Vitaly Kuznetsov
Michal Hocko writes: > On Mon 13-03-17 11:55:54, Igor Mammedov wrote: >> > > >> > >- suggested RFC is not acceptable from virt point of view >> > > as it regresses guests on top of x86 kvm/vmware which >> > > both use ACPI based memory hotplug. >> > > >> > >- u

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-13 Thread Michal Hocko
On Mon 13-03-17 11:55:54, Igor Mammedov wrote: > On Thu, 9 Mar 2017 13:54:00 +0100 > Michal Hocko wrote: > > [...] > > > It's major regression if you remove auto online in kernels that > > > run on top of x86 kvm/vmware hypervisors, making API cleanups > > > while breaking useful functionality do

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-13 Thread Igor Mammedov
On Thu, 9 Mar 2017 13:54:00 +0100 Michal Hocko wrote: [...] > > It's major regression if you remove auto online in kernels that > > run on top of x86 kvm/vmware hypervisors, making API cleanups > > while breaking useful functionality doesn't make sense. > > > > I would ACK config option removal

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-10 Thread Daniel Kiper
Hey, On Mon, Mar 06, 2017 at 03:54:17PM +0100, Michal Hocko wrote: [...] > So let's discuss the current memory hotplug shortcomings and get rid of > the crud which developed on top. I will start by splitting up the patch > into 3 parts. Do the auto online thing from the HyperV and xen balloning

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-09 Thread Michal Hocko
On Tue 07-03-17 13:40:04, Igor Mammedov wrote: > On Mon, 6 Mar 2017 15:54:17 +0100 > Michal Hocko wrote: > > > On Fri 03-03-17 18:34:22, Igor Mammedov wrote: [...] > > > in current mainline kernel it triggers following code path: > > > > > > online_pages() > > > ... > > >if (online_typ

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-07 Thread Igor Mammedov
On Mon, 6 Mar 2017 15:54:17 +0100 Michal Hocko wrote: > On Fri 03-03-17 18:34:22, Igor Mammedov wrote: > > On Fri, 3 Mar 2017 09:27:23 +0100 > > Michal Hocko wrote: > > > > > On Thu 02-03-17 18:03:15, Igor Mammedov wrote: > > > > On Thu, 2 Mar 2017 15:28:16 +0100 > > > > Michal Hocko wrote

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-06 Thread Michal Hocko
On Fri 03-03-17 18:34:22, Igor Mammedov wrote: > On Fri, 3 Mar 2017 09:27:23 +0100 > Michal Hocko wrote: > > > On Thu 02-03-17 18:03:15, Igor Mammedov wrote: > > > On Thu, 2 Mar 2017 15:28:16 +0100 > > > Michal Hocko wrote: > > > > > > > On Thu 02-03-17 14:53:48, Igor Mammedov wrote: > > > >

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-03 Thread Igor Mammedov
On Fri, 3 Mar 2017 09:27:23 +0100 Michal Hocko wrote: > On Thu 02-03-17 18:03:15, Igor Mammedov wrote: > > On Thu, 2 Mar 2017 15:28:16 +0100 > > Michal Hocko wrote: > > > > > On Thu 02-03-17 14:53:48, Igor Mammedov wrote: > > > [...] > > > > When trying to support memory unplug on guest sid

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-03 Thread Michal Hocko
On Thu 02-03-17 18:03:15, Igor Mammedov wrote: > On Thu, 2 Mar 2017 15:28:16 +0100 > Michal Hocko wrote: > > > On Thu 02-03-17 14:53:48, Igor Mammedov wrote: > > [...] > > > When trying to support memory unplug on guest side in RHEL7, > > > experience shows otherwise. Simplistic udev rule which o

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-02 Thread Igor Mammedov
On Thu, 2 Mar 2017 15:28:16 +0100 Michal Hocko wrote: > On Thu 02-03-17 14:53:48, Igor Mammedov wrote: > [...] > > When trying to support memory unplug on guest side in RHEL7, > > experience shows otherwise. Simplistic udev rule which onlines > > added block doesn't work in case one wants to onli

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-02 Thread Michal Hocko
On Thu 02-03-17 14:53:48, Igor Mammedov wrote: [...] > When trying to support memory unplug on guest side in RHEL7, > experience shows otherwise. Simplistic udev rule which onlines > added block doesn't work in case one wants to online it as movable. > > Hotplugged blocks in current kernel should

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-03-02 Thread Igor Mammedov
On Mon 27-02-17 16:43:04, Michal Hocko wrote: > On Mon 27-02-17 12:25:10, Heiko Carstens wrote: > > On Mon, Feb 27, 2017 at 11:02:09AM +0100, Vitaly Kuznetsov wrote: > > > A couple of other thoughts: > > > 1) Having all newly added memory online ASAP is probably what people > > > want for all vir

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-28 Thread Heiko Carstens
On Mon, Feb 27, 2017 at 04:43:04PM +0100, Michal Hocko wrote: > On Mon 27-02-17 12:25:10, Heiko Carstens wrote: > > On Mon, Feb 27, 2017 at 11:02:09AM +0100, Vitaly Kuznetsov wrote: > > > A couple of other thoughts: > > > 1) Having all newly added memory online ASAP is probably what people > > > wa

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Michal Hocko
On Mon 27-02-17 11:28:52, Reza Arbab wrote: > On Mon, Feb 27, 2017 at 10:28:17AM +0100, Michal Hocko wrote: > >diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h > >index 134a2f69c21a..a72f7f64ee26 100644 > >--- a/include/linux/memory_hotplug.h > >+++ b/include/linux/memor

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Reza Arbab
On Mon, Feb 27, 2017 at 10:28:17AM +0100, Michal Hocko wrote: diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 134a2f69c21a..a72f7f64ee26 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -100,8 +100,6 @@ extern void __online_pag

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Michal Hocko
On Mon 27-02-17 12:25:10, Heiko Carstens wrote: > On Mon, Feb 27, 2017 at 11:02:09AM +0100, Vitaly Kuznetsov wrote: > > A couple of other thoughts: > > 1) Having all newly added memory online ASAP is probably what people > > want for all virtual machines. > > This is not true for s390. On s390 we

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Vitaly Kuznetsov
Michal Hocko writes: > On Mon 27-02-17 11:49:43, Vitaly Kuznetsov wrote: >> Michal Hocko writes: >> >> > On Mon 27-02-17 11:02:09, Vitaly Kuznetsov wrote: >> > [...] >> >> I don't have anything new to add to the discussion happened last week >> >> but I'd like to summarize my arguments against

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Michal Hocko
On Mon 27-02-17 11:49:43, Vitaly Kuznetsov wrote: > Michal Hocko writes: > > > On Mon 27-02-17 11:02:09, Vitaly Kuznetsov wrote: > > [...] > >> I don't have anything new to add to the discussion happened last week > >> but I'd like to summarize my arguments against this change: > >> > >> 1) This

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Vitaly Kuznetsov
Heiko Carstens writes: > On Mon, Feb 27, 2017 at 11:02:09AM +0100, Vitaly Kuznetsov wrote: >> A couple of other thoughts: >> 1) Having all newly added memory online ASAP is probably what people >> want for all virtual machines. Sorry, obviously missed 'x86' in the above statement. > > This is n

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Heiko Carstens
On Mon, Feb 27, 2017 at 11:02:09AM +0100, Vitaly Kuznetsov wrote: > A couple of other thoughts: > 1) Having all newly added memory online ASAP is probably what people > want for all virtual machines. This is not true for s390. On s390 we have "standby" memory that a guest sees and potentially may

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Vitaly Kuznetsov
Michal Hocko writes: > On Mon 27-02-17 11:02:09, Vitaly Kuznetsov wrote: > [...] >> I don't have anything new to add to the discussion happened last week >> but I'd like to summarize my arguments against this change: >> >> 1) This patch doesn't solve any issue. Configuration option is not an >>

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Michal Hocko
On Mon 27-02-17 11:02:09, Vitaly Kuznetsov wrote: [...] > I don't have anything new to add to the discussion happened last week > but I'd like to summarize my arguments against this change: > > 1) This patch doesn't solve any issue. Configuration option is not an > issue by itself, it is an option

Re: [Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Vitaly Kuznetsov
Michal Hocko writes: > From: Michal Hocko > > This knob has been added by 31bc3858ea3e ("memory-hotplug: add automatic > onlining policy for the newly added memory") mainly to cover memory > hotplug based balooning solutions currently implemented for HyperV > and Xen. Both of them want to online

[Xen-devel] [RFC PATCH] mm, hotplug: get rid of auto_online_blocks

2017-02-27 Thread Michal Hocko
From: Michal Hocko This knob has been added by 31bc3858ea3e ("memory-hotplug: add automatic onlining policy for the newly added memory") mainly to cover memory hotplug based balooning solutions currently implemented for HyperV and Xen. Both of them want to online the memory as soon after register