Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-26 Thread Michal Hocko
[Sorry to jump in that late] On Tue 20-11-12 10:02:45, David Rientjes wrote: > On Mon, 19 Nov 2012, Glauber Costa wrote: > > > >> In the case I outlined below, for backwards compatibility. What I > > >> actually mean is that memcg *currently* allows arbitrary notifications. > > >> One way to

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-26 Thread Michal Hocko
[Sorry to jump in that late] On Tue 20-11-12 10:02:45, David Rientjes wrote: On Mon, 19 Nov 2012, Glauber Costa wrote: In the case I outlined below, for backwards compatibility. What I actually mean is that memcg *currently* allows arbitrary notifications. One way to merge those,

RE: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread leonid.moiseichuk
-Original Message- From: ext Kirill A. Shutemov [mailto:kir...@shutemov.name] Sent: 21 November, 2012 11:31 ... BTW, there's interface for OOM notification in memcg. See oom_control. I guess other pressure levels can also fit to the interface. --- Hi, I have tracking this conversation

RE: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread leonid.moiseichuk
-Original Message- From: ext Glauber Costa [mailto:glom...@parallels.com] Sent: 21 November, 2012 13:55 So I'll say it again: if this is always global, there is no reason any cgroup needs to be involved. If this turns out to be per-process, as Anton suggested in a recent e-mail, I

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Glauber Costa
Hi, > > Memory notifications are quite irrelevant to partitioning and cgroups. The > use-case is related to user-space handling low memory. Meaning the > functionality should be accurate with specific granularity (e.g. 1 MB) and > time (0.25s is OK) but better to have it as simple and

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Kirill A. Shutemov
On Tue, Nov 20, 2012 at 10:02:45AM -0800, David Rientjes wrote: > On Mon, 19 Nov 2012, Glauber Costa wrote: > > > >> In the case I outlined below, for backwards compatibility. What I > > >> actually mean is that memcg *currently* allows arbitrary notifications. > > >> One way to merge those,

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Glauber Costa
On 11/21/2012 12:46 PM, Anton Vorontsov wrote: > On Wed, Nov 21, 2012 at 12:27:28PM +0400, Glauber Costa wrote: >> On 11/20/2012 10:23 PM, David Rientjes wrote: >>> Anton can correct me if I'm wrong, but I certainly don't think this is >>> where mempressure is headed: I don't think any accounting

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Anton Vorontsov
On Wed, Nov 21, 2012 at 12:27:28PM +0400, Glauber Costa wrote: > On 11/20/2012 10:23 PM, David Rientjes wrote: > > Anton can correct me if I'm wrong, but I certainly don't think this is > > where mempressure is headed: I don't think any accounting needs to be done Yup, I'd rather not do any

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Glauber Costa
On 11/20/2012 10:23 PM, David Rientjes wrote: > Anton can correct me if I'm wrong, but I certainly don't think this is > where mempressure is headed: I don't think any accounting needs to be done > and, if it is, it's a design issue that should be addressed now rather > than later. I believe

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Glauber Costa
On 11/20/2012 10:23 PM, David Rientjes wrote: Anton can correct me if I'm wrong, but I certainly don't think this is where mempressure is headed: I don't think any accounting needs to be done and, if it is, it's a design issue that should be addressed now rather than later. I believe

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Anton Vorontsov
On Wed, Nov 21, 2012 at 12:27:28PM +0400, Glauber Costa wrote: On 11/20/2012 10:23 PM, David Rientjes wrote: Anton can correct me if I'm wrong, but I certainly don't think this is where mempressure is headed: I don't think any accounting needs to be done Yup, I'd rather not do any

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Glauber Costa
On 11/21/2012 12:46 PM, Anton Vorontsov wrote: On Wed, Nov 21, 2012 at 12:27:28PM +0400, Glauber Costa wrote: On 11/20/2012 10:23 PM, David Rientjes wrote: Anton can correct me if I'm wrong, but I certainly don't think this is where mempressure is headed: I don't think any accounting needs to

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Kirill A. Shutemov
On Tue, Nov 20, 2012 at 10:02:45AM -0800, David Rientjes wrote: On Mon, 19 Nov 2012, Glauber Costa wrote: In the case I outlined below, for backwards compatibility. What I actually mean is that memcg *currently* allows arbitrary notifications. One way to merge those, while moving to a

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread Glauber Costa
Hi, Memory notifications are quite irrelevant to partitioning and cgroups. The use-case is related to user-space handling low memory. Meaning the functionality should be accurate with specific granularity (e.g. 1 MB) and time (0.25s is OK) but better to have it as simple and

RE: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread leonid.moiseichuk
-Original Message- From: ext Glauber Costa [mailto:glom...@parallels.com] Sent: 21 November, 2012 13:55 So I'll say it again: if this is always global, there is no reason any cgroup needs to be involved. If this turns out to be per-process, as Anton suggested in a recent e-mail, I

RE: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-21 Thread leonid.moiseichuk
-Original Message- From: ext Kirill A. Shutemov [mailto:kir...@shutemov.name] Sent: 21 November, 2012 11:31 ... BTW, there's interface for OOM notification in memcg. See oom_control. I guess other pressure levels can also fit to the interface. --- Hi, I have tracking this conversation

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-20 Thread David Rientjes
On Mon, 19 Nov 2012, Glauber Costa wrote: > >> Because cpusets only deal with memory placement, not memory usage. > > > > The set of nodes that a thread is allowed to allocate from may face memory > > pressure up to and including oom while the rest of the system may have a > > ton of free

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-20 Thread David Rientjes
On Mon, 19 Nov 2012, Glauber Costa wrote: > >> In the case I outlined below, for backwards compatibility. What I > >> actually mean is that memcg *currently* allows arbitrary notifications. > >> One way to merge those, while moving to a saner 3-point notification, is > >> to still allow the old

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-20 Thread David Rientjes
On Mon, 19 Nov 2012, Glauber Costa wrote: In the case I outlined below, for backwards compatibility. What I actually mean is that memcg *currently* allows arbitrary notifications. One way to merge those, while moving to a saner 3-point notification, is to still allow the old writes and

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-20 Thread David Rientjes
On Mon, 19 Nov 2012, Glauber Costa wrote: Because cpusets only deal with memory placement, not memory usage. The set of nodes that a thread is allowed to allocate from may face memory pressure up to and including oom while the rest of the system may have a ton of free memory. Your

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-19 Thread Glauber Costa
>>> Umm, why do users of cpusets not want to be able to trigger memory >>> pressure notifications? >>> >> Because cpusets only deal with memory placement, not memory usage. > > The set of nodes that a thread is allowed to allocate from may face memory > pressure up to and including oom while

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-19 Thread Glauber Costa
On 11/17/2012 05:21 AM, Anton Vorontsov wrote: > On Fri, Nov 16, 2012 at 01:57:09PM -0800, David Rientjes wrote: I'm wondering if we should have more than three different levels. >>> >>> In the case I outlined below, for backwards compatibility. What I >>> actually mean is that memcg

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-19 Thread Glauber Costa
On 11/17/2012 01:57 AM, David Rientjes wrote: > On Sat, 17 Nov 2012, Glauber Costa wrote: > >>> I'm wondering if we should have more than three different levels. >>> >> >> In the case I outlined below, for backwards compatibility. What I >> actually mean is that memcg *currently* allows arbitrary

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-19 Thread Glauber Costa
On 11/17/2012 01:57 AM, David Rientjes wrote: On Sat, 17 Nov 2012, Glauber Costa wrote: I'm wondering if we should have more than three different levels. In the case I outlined below, for backwards compatibility. What I actually mean is that memcg *currently* allows arbitrary

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-19 Thread Glauber Costa
On 11/17/2012 05:21 AM, Anton Vorontsov wrote: On Fri, Nov 16, 2012 at 01:57:09PM -0800, David Rientjes wrote: I'm wondering if we should have more than three different levels. In the case I outlined below, for backwards compatibility. What I actually mean is that memcg *currently* allows

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-19 Thread Glauber Costa
Umm, why do users of cpusets not want to be able to trigger memory pressure notifications? Because cpusets only deal with memory placement, not memory usage. The set of nodes that a thread is allowed to allocate from may face memory pressure up to and including oom while the rest of the

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-18 Thread David Rientjes
On Fri, 16 Nov 2012, Anton Vorontsov wrote: > The main change is that I decided to go with discrete levels of the > pressure. > > When I started writing the man page, I had to describe the 'reclaimer > inefficiency index', and while doing this I realized that I'm describing > how the kernel

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-18 Thread David Rientjes
On Fri, 16 Nov 2012, Anton Vorontsov wrote: The main change is that I decided to go with discrete levels of the pressure. When I started writing the man page, I had to describe the 'reclaimer inefficiency index', and while doing this I realized that I'm describing how the kernel is

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread Anton Vorontsov
On Fri, Nov 16, 2012 at 01:57:09PM -0800, David Rientjes wrote: > > > I'm wondering if we should have more than three different levels. > > > > > > > In the case I outlined below, for backwards compatibility. What I > > actually mean is that memcg *currently* allows arbitrary notifications. > >

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread David Rientjes
On Sat, 17 Nov 2012, Glauber Costa wrote: > > I'm wondering if we should have more than three different levels. > > > > In the case I outlined below, for backwards compatibility. What I > actually mean is that memcg *currently* allows arbitrary notifications. > One way to merge those, while

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread Glauber Costa
Hey, On 11/17/2012 12:04 AM, David Rientjes wrote: > On Fri, 16 Nov 2012, Glauber Costa wrote: > >> My personal take: >> >> Most people hate memcg due to the cost it imposes. I've already >> demonstrated that with some effort, it doesn't necessarily have to be >> so.

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread David Rientjes
On Fri, 16 Nov 2012, Glauber Costa wrote: > My personal take: > > Most people hate memcg due to the cost it imposes. I've already > demonstrated that with some effort, it doesn't necessarily have to be > so. (http://lwn.net/Articles/517634/) > > The one thing I missed on that work, was

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread Glauber Costa
On 11/16/2012 01:25 AM, David Rientjes wrote: > On Thu, 15 Nov 2012, Anton Vorontsov wrote: > >> Hehe, you're saying that we have to have cgroups=y. :) But some folks were >> deliberately asking us to make the cgroups optional. >> > > Enabling just CONFIG_CGROUPS (which is enabled by default)

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread Glauber Costa
On 11/16/2012 01:25 AM, David Rientjes wrote: On Thu, 15 Nov 2012, Anton Vorontsov wrote: Hehe, you're saying that we have to have cgroups=y. :) But some folks were deliberately asking us to make the cgroups optional. Enabling just CONFIG_CGROUPS (which is enabled by default) and no other

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread David Rientjes
On Fri, 16 Nov 2012, Glauber Costa wrote: My personal take: Most people hate memcg due to the cost it imposes. I've already demonstrated that with some effort, it doesn't necessarily have to be so. (http://lwn.net/Articles/517634/) The one thing I missed on that work, was precisely

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread Glauber Costa
Hey, On 11/17/2012 12:04 AM, David Rientjes wrote: On Fri, 16 Nov 2012, Glauber Costa wrote: My personal take: Most people hate memcg due to the cost it imposes. I've already demonstrated that with some effort, it doesn't necessarily have to be so. (http://lwn.net/Articles/517634/) The

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread David Rientjes
On Sat, 17 Nov 2012, Glauber Costa wrote: I'm wondering if we should have more than three different levels. In the case I outlined below, for backwards compatibility. What I actually mean is that memcg *currently* allows arbitrary notifications. One way to merge those, while moving to a

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-16 Thread Anton Vorontsov
On Fri, Nov 16, 2012 at 01:57:09PM -0800, David Rientjes wrote: I'm wondering if we should have more than three different levels. In the case I outlined below, for backwards compatibility. What I actually mean is that memcg *currently* allows arbitrary notifications. One way to

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-15 Thread David Rientjes
On Thu, 15 Nov 2012, Anton Vorontsov wrote: > Hehe, you're saying that we have to have cgroups=y. :) But some folks were > deliberately asking us to make the cgroups optional. > Enabling just CONFIG_CGROUPS (which is enabled by default) and no other current cgroups increases the size of the

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-15 Thread Anton Vorontsov
On Thu, Nov 15, 2012 at 12:11:47AM -0800, David Rientjes wrote: [...] > Might not be too difficult if you implement your own cgroup to aggregate > these tasks for which you want to know memory pressure events; it would > have to be triggered for the task trying to allocate memory at any given >

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-15 Thread David Rientjes
On Wed, 14 Nov 2012, Anton Vorontsov wrote: > Thanks again for your inspirational comments! > Heh, not sure I've been too inspirational (probably more annoying than anything else). I really do want generic memory pressure notifications in the kernel and already have some ideas on how I can

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-15 Thread David Rientjes
On Wed, 14 Nov 2012, Anton Vorontsov wrote: Thanks again for your inspirational comments! Heh, not sure I've been too inspirational (probably more annoying than anything else). I really do want generic memory pressure notifications in the kernel and already have some ideas on how I can tie

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-15 Thread Anton Vorontsov
On Thu, Nov 15, 2012 at 12:11:47AM -0800, David Rientjes wrote: [...] Might not be too difficult if you implement your own cgroup to aggregate these tasks for which you want to know memory pressure events; it would have to be triggered for the task trying to allocate memory at any given

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-15 Thread David Rientjes
On Thu, 15 Nov 2012, Anton Vorontsov wrote: Hehe, you're saying that we have to have cgroups=y. :) But some folks were deliberately asking us to make the cgroups optional. Enabling just CONFIG_CGROUPS (which is enabled by default) and no other current cgroups increases the size of the

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread Anton Vorontsov
Hi David, Thanks again for your inspirational comments! On Wed, Nov 14, 2012 at 07:59:52PM -0800, David Rientjes wrote: > > > I agree that eventfd is the way to go, but I'll also add that this > > > feature > > > seems to be implemented at a far too coarse of level. Memory, and hence > > >

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread David Rientjes
On Wed, 14 Nov 2012, Anton Vorontsov wrote: > > I agree that eventfd is the way to go, but I'll also add that this feature > > seems to be implemented at a far too coarse of level. Memory, and hence > > memory pressure, is constrained by several factors other than just the > > amount of

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread Anton Vorontsov
Hi David, Thanks for your comments! On Wed, Nov 14, 2012 at 07:21:14PM -0800, David Rientjes wrote: > > > Why should you be required to use cgroups to get VM pressure events to > > > userspace? > > > > Valid point. But in fact you have it on most systems anyway. > > > > I personally don't like

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread David Rientjes
On Wed, 7 Nov 2012, Kirill A. Shutemov wrote: > > > Sorry, I didn't follow previous discussion on this, but could you > > > explain what's wrong with memory notifications from memcg? > > > As I can see you can get pretty similar functionality using memory > > > thresholds on the root cgroup.

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread David Rientjes
On Wed, 7 Nov 2012, Kirill A. Shutemov wrote: Sorry, I didn't follow previous discussion on this, but could you explain what's wrong with memory notifications from memcg? As I can see you can get pretty similar functionality using memory thresholds on the root cgroup. What's the

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread Anton Vorontsov
Hi David, Thanks for your comments! On Wed, Nov 14, 2012 at 07:21:14PM -0800, David Rientjes wrote: Why should you be required to use cgroups to get VM pressure events to userspace? Valid point. But in fact you have it on most systems anyway. I personally don't like to have a

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread David Rientjes
On Wed, 14 Nov 2012, Anton Vorontsov wrote: I agree that eventfd is the way to go, but I'll also add that this feature seems to be implemented at a far too coarse of level. Memory, and hence memory pressure, is constrained by several factors other than just the amount of physical RAM

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-14 Thread Anton Vorontsov
Hi David, Thanks again for your inspirational comments! On Wed, Nov 14, 2012 at 07:59:52PM -0800, David Rientjes wrote: I agree that eventfd is the way to go, but I'll also add that this feature seems to be implemented at a far too coarse of level. Memory, and hence memory

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-09 Thread Anton Vorontsov
On Fri, Nov 09, 2012 at 09:32:03AM +0100, Luiz Capitulino wrote: > Anton Vorontsov wrote: > > This is the third RFC. As suggested by Minchan Kim, the API is much > > simplified now (comparing to vmevent_fd): > > Which tree is this against? I'd like to try this series, but it doesn't > apply to

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-09 Thread Luiz Capitulino
Hi Anton, On Wed, 7 Nov 2012 02:53:49 -0800 Anton Vorontsov wrote: > Hi all, > > This is the third RFC. As suggested by Minchan Kim, the API is much > simplified now (comparing to vmevent_fd): Which tree is this against? I'd like to try this series, but it doesn't apply to Linus tree. -- To

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-09 Thread Luiz Capitulino
Hi Anton, On Wed, 7 Nov 2012 02:53:49 -0800 Anton Vorontsov anton.voront...@linaro.org wrote: Hi all, This is the third RFC. As suggested by Minchan Kim, the API is much simplified now (comparing to vmevent_fd): Which tree is this against? I'd like to try this series, but it doesn't apply

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-09 Thread Anton Vorontsov
On Fri, Nov 09, 2012 at 09:32:03AM +0100, Luiz Capitulino wrote: Anton Vorontsov anton.voront...@linaro.org wrote: This is the third RFC. As suggested by Minchan Kim, the API is much simplified now (comparing to vmevent_fd): Which tree is this against? I'd like to try this series, but it

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
Hi Greg, On 11/7/12 7:20 PM, Greg Thelen wrote: > Related question: are there plans to extend this system call to > provide per-cgroup vm pressure notification? Yes, that's something that needs to be addressed before we can ever consider merging something like this to mainline. We probably

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Greg Thelen
On Wed, Nov 07 2012, Kirill A. Shutemov wrote: > On Wed, Nov 07, 2012 at 02:53:49AM -0800, Anton Vorontsov wrote: >> Hi all, >> >> This is the third RFC. As suggested by Minchan Kim, the API is much >> simplified now (comparing to vmevent_fd): >> >> - As well as Minchan, KOSAKI Motohiro didn't

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
On Wed, Nov 07, 2012 at 02:11:10PM +0200, Kirill A. Shutemov wrote: [...] > >We can have plenty of "free" memory, of which say 90% will be caches, > >and say 10% idle. But we do want to differentiate these types of memory > >(although not going into details about it), i.e. we want to

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
On Wed, Nov 07, 2012 at 01:30:16PM +0200, Pekka Enberg wrote: [...] > I love the API and implementation simplifications but I hate the new > ABI. It's a specialized, single-purpose syscall and bunch of procfs > tunables and I don't see how it's 'extensible' to anything but VM It is extensible to

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Kirill A. Shutemov
On Wed, Nov 07, 2012 at 03:43:46AM -0800, Anton Vorontsov wrote: > On Wed, Nov 07, 2012 at 01:21:36PM +0200, Kirill A. Shutemov wrote: > [...] > > Sorry, I didn't follow previous discussion on this, but could you > > explain what's wrong with memory notifications from memcg? > > As I can see you

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
On Wed, Nov 07, 2012 at 01:21:36PM +0200, Kirill A. Shutemov wrote: [...] > Sorry, I didn't follow previous discussion on this, but could you > explain what's wrong with memory notifications from memcg? > As I can see you can get pretty similar functionality using memory > thresholds on the root

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Kirill A. Shutemov
On Wed, Nov 07, 2012 at 01:28:12PM +0200, Pekka Enberg wrote: > On Wed, Nov 7, 2012 at 1:21 PM, Kirill A. Shutemov > wrote: > >> While the new API is very simple, it is still extensible (i.e. versioned). > > > > Sorry, I didn't follow previous discussion on this, but could you > > explain what's

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
On Wed, Nov 7, 2012 at 1:30 PM, Pekka Enberg wrote: > I love the API and implementation simplifications but I hate the new > ABI. It's a specialized, single-purpose syscall and bunch of procfs > tunables and I don't see how it's 'extensible' to anything but VM s/anything but VM/anything but VM

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
Hi Anton, On Wed, Nov 7, 2012 at 12:53 PM, Anton Vorontsov wrote: > This is the third RFC. As suggested by Minchan Kim, the API is much > simplified now (comparing to vmevent_fd): > > - As well as Minchan, KOSAKI Motohiro didn't like the timers, so the > timers are gone now; > - Pekka Enberg

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
On Wed, Nov 7, 2012 at 1:21 PM, Kirill A. Shutemov wrote: >> While the new API is very simple, it is still extensible (i.e. versioned). > > Sorry, I didn't follow previous discussion on this, but could you > explain what's wrong with memory notifications from memcg? > As I can see you can get

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Kirill A. Shutemov
On Wed, Nov 07, 2012 at 02:53:49AM -0800, Anton Vorontsov wrote: > Hi all, > > This is the third RFC. As suggested by Minchan Kim, the API is much > simplified now (comparing to vmevent_fd): > > - As well as Minchan, KOSAKI Motohiro didn't like the timers, so the > timers are gone now; > -

[RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
Hi all, This is the third RFC. As suggested by Minchan Kim, the API is much simplified now (comparing to vmevent_fd): - As well as Minchan, KOSAKI Motohiro didn't like the timers, so the timers are gone now; - Pekka Enberg didn't like the complex attributes matching code, and so it is no

[RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
Hi all, This is the third RFC. As suggested by Minchan Kim, the API is much simplified now (comparing to vmevent_fd): - As well as Minchan, KOSAKI Motohiro didn't like the timers, so the timers are gone now; - Pekka Enberg didn't like the complex attributes matching code, and so it is no

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Kirill A. Shutemov
On Wed, Nov 07, 2012 at 02:53:49AM -0800, Anton Vorontsov wrote: Hi all, This is the third RFC. As suggested by Minchan Kim, the API is much simplified now (comparing to vmevent_fd): - As well as Minchan, KOSAKI Motohiro didn't like the timers, so the timers are gone now; - Pekka

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
On Wed, Nov 7, 2012 at 1:21 PM, Kirill A. Shutemov kir...@shutemov.name wrote: While the new API is very simple, it is still extensible (i.e. versioned). Sorry, I didn't follow previous discussion on this, but could you explain what's wrong with memory notifications from memcg? As I can see

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
Hi Anton, On Wed, Nov 7, 2012 at 12:53 PM, Anton Vorontsov anton.voront...@linaro.org wrote: This is the third RFC. As suggested by Minchan Kim, the API is much simplified now (comparing to vmevent_fd): - As well as Minchan, KOSAKI Motohiro didn't like the timers, so the timers are gone

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
On Wed, Nov 7, 2012 at 1:30 PM, Pekka Enberg penb...@kernel.org wrote: I love the API and implementation simplifications but I hate the new ABI. It's a specialized, single-purpose syscall and bunch of procfs tunables and I don't see how it's 'extensible' to anything but VM s/anything but

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Kirill A. Shutemov
On Wed, Nov 07, 2012 at 01:28:12PM +0200, Pekka Enberg wrote: On Wed, Nov 7, 2012 at 1:21 PM, Kirill A. Shutemov kir...@shutemov.name wrote: While the new API is very simple, it is still extensible (i.e. versioned). Sorry, I didn't follow previous discussion on this, but could you

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
On Wed, Nov 07, 2012 at 01:21:36PM +0200, Kirill A. Shutemov wrote: [...] Sorry, I didn't follow previous discussion on this, but could you explain what's wrong with memory notifications from memcg? As I can see you can get pretty similar functionality using memory thresholds on the root

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Kirill A. Shutemov
On Wed, Nov 07, 2012 at 03:43:46AM -0800, Anton Vorontsov wrote: On Wed, Nov 07, 2012 at 01:21:36PM +0200, Kirill A. Shutemov wrote: [...] Sorry, I didn't follow previous discussion on this, but could you explain what's wrong with memory notifications from memcg? As I can see you can get

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
On Wed, Nov 07, 2012 at 01:30:16PM +0200, Pekka Enberg wrote: [...] I love the API and implementation simplifications but I hate the new ABI. It's a specialized, single-purpose syscall and bunch of procfs tunables and I don't see how it's 'extensible' to anything but VM It is extensible to VM

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Anton Vorontsov
On Wed, Nov 07, 2012 at 02:11:10PM +0200, Kirill A. Shutemov wrote: [...] We can have plenty of free memory, of which say 90% will be caches, and say 10% idle. But we do want to differentiate these types of memory (although not going into details about it), i.e. we want to get

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Greg Thelen
On Wed, Nov 07 2012, Kirill A. Shutemov wrote: On Wed, Nov 07, 2012 at 02:53:49AM -0800, Anton Vorontsov wrote: Hi all, This is the third RFC. As suggested by Minchan Kim, the API is much simplified now (comparing to vmevent_fd): - As well as Minchan, KOSAKI Motohiro didn't like the

Re: [RFC v3 0/3] vmpressure_fd: Linux VM pressure notifications

2012-11-07 Thread Pekka Enberg
Hi Greg, On 11/7/12 7:20 PM, Greg Thelen wrote: Related question: are there plans to extend this system call to provide per-cgroup vm pressure notification? Yes, that's something that needs to be addressed before we can ever consider merging something like this to mainline. We probably need