Re: [PATCH 3/3] mm: idle memory tracking

2015-03-19 Thread Cyrill Gorcunov 
On Thu, Mar 19, 2015 at 01:41:03PM +0300, Vladimir Davydov wrote:
> > 
> > Vladimir, might we need get_online_mems/put_online_mems here,
> > or if node gets offline this wont be a problem? (Asking
> > because i don't know).
> 
> I only need to dereference page structs corresponding to the node here,
> and page structs are not freed when the node gets offline AFAICS, so I
> guess it must be safe.

OK, thanks for info!
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Re: [PATCH 3/3] mm: idle memory tracking

2015-03-19 Thread Vladimir Davydov 
On Thu, Mar 19, 2015 at 01:12:05PM +0300, Cyrill Gorcunov wrote:
> On Wed, Mar 18, 2015 at 11:44:36PM +0300, Vladimir Davydov wrote:
> > +static void set_mem_idle(void)
> > +{
> > +   int nid;
> > +
> > +   for_each_online_node(nid)
> > +   set_mem_idle_node(nid);
> > +}
> 
> Vladimir, might we need get_online_mems/put_online_mems here,
> or if node gets offline this wont be a problem? (Asking
> because i don't know).

I only need to dereference page structs corresponding to the node here,
and page structs are not freed when the node gets offline AFAICS, so I
guess it must be safe.

Thanks,
Vladimir
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Re: [PATCH 3/3] mm: idle memory tracking

2015-03-19 Thread Cyrill Gorcunov 
On Wed, Mar 18, 2015 at 11:44:36PM +0300, Vladimir Davydov wrote:
> Knowing the portion of memory that is not used by a certain application
> or memory cgroup (idle memory) can be useful for partitioning the system
> efficiently. Currently, the only means to estimate the amount of idle
> memory provided by the kernel is /proc/PID/clear_refs. However, it has
> two serious shortcomings:
> 
>  - it does not count unmapped file pages
>  - it affects the reclaimer logic
> 
> This patch attempts to provide the userspace with the means to track
> idle memory without the above mentioned limitations.
...
> +static void set_mem_idle(void)
> +{
> + int nid;
> +
> + for_each_online_node(nid)
> + set_mem_idle_node(nid);
> +}

Vladimir, might we need get_online_mems/put_online_mems here,
or if node gets offline this wont be a problem? (Asking
because i don't know).
--
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the body of a message to majord...@vger.kernel.org
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Re: [PATCH 3/3] mm: idle memory tracking

2015-03-19 Thread Vladimir Davydov 
On Thu, Mar 19, 2015 at 01:12:05PM +0300, Cyrill Gorcunov wrote:
 On Wed, Mar 18, 2015 at 11:44:36PM +0300, Vladimir Davydov wrote:
  +static void set_mem_idle(void)
  +{
  +   int nid;
  +
  +   for_each_online_node(nid)
  +   set_mem_idle_node(nid);
  +}
 
 Vladimir, might we need get_online_mems/put_online_mems here,
 or if node gets offline this wont be a problem? (Asking
 because i don't know).

I only need to dereference page structs corresponding to the node here,
and page structs are not freed when the node gets offline AFAICS, so I
guess it must be safe.

Thanks,
Vladimir
--
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the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 3/3] mm: idle memory tracking

2015-03-19 Thread Cyrill Gorcunov 
On Thu, Mar 19, 2015 at 01:41:03PM +0300, Vladimir Davydov wrote:
  
  Vladimir, might we need get_online_mems/put_online_mems here,
  or if node gets offline this wont be a problem? (Asking
  because i don't know).
 
 I only need to dereference page structs corresponding to the node here,
 and page structs are not freed when the node gets offline AFAICS, so I
 guess it must be safe.

OK, thanks for info!
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 3/3] mm: idle memory tracking

2015-03-19 Thread Cyrill Gorcunov 
On Wed, Mar 18, 2015 at 11:44:36PM +0300, Vladimir Davydov wrote:
 Knowing the portion of memory that is not used by a certain application
 or memory cgroup (idle memory) can be useful for partitioning the system
 efficiently. Currently, the only means to estimate the amount of idle
 memory provided by the kernel is /proc/PID/clear_refs. However, it has
 two serious shortcomings:
 
  - it does not count unmapped file pages
  - it affects the reclaimer logic
 
 This patch attempts to provide the userspace with the means to track
 idle memory without the above mentioned limitations.
...
 +static void set_mem_idle(void)
 +{
 + int nid;
 +
 + for_each_online_node(nid)
 + set_mem_idle_node(nid);
 +}

Vladimir, might we need get_online_mems/put_online_mems here,
or if node gets offline this wont be a problem? (Asking
because i don't know).
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/