[PATCH] mm/thp: fix comments in transparent_hugepage_flags

[PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Jianguo Wu]

Since commit d39d33c332(thp: enable direct defrag), defrag is enable
for all transparent hugepage page faults by default, not only in
MADV_HUGEPAGE regions.

Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
---
 mm/huge_memory.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a92012a..abf047e 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -28,10 +28,8 @@
 
 /*
  * By default transparent hugepage support is enabled for all mappings
- * and khugepaged scans all mappings. Defrag is only invoked by
- * khugepaged hugepage allocations and by page faults inside
- * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
- * allocations.
+ * and khugepaged scans all mappings. Defrag is invoked by khugepaged
+ * hugepage allocations and by page faults for all hugepage allocations.
  */
 unsigned long transparent_hugepage_flags __read_mostly =
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
-- 
1.8.1.2

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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

Hi Jianguo,
On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>for all transparent hugepage page faults by default, not only in
>MADV_HUGEPAGE regions.
>
>Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>---
> mm/huge_memory.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
>diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>index a92012a..abf047e 100644
>--- a/mm/huge_memory.c
>+++ b/mm/huge_memory.c
>@@ -28,10 +28,8 @@
>
> /*
>  * By default transparent hugepage support is enabled for all mappings

This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
order that avoid to risk increase the memory footprint of applications w/o a 
guaranteed benefit.

Regards,
Wanpeng Li 

>- * and khugepaged scans all mappings. Defrag is only invoked by
>- * khugepaged hugepage allocations and by page faults inside
>- * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>- * allocations.
>+ * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>+ * hugepage allocations and by page faults for all hugepage allocations.
>  */
> unsigned long transparent_hugepage_flags __read_mostly =
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>-- 
>1.8.1.2
>
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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

Hi Jianguo,
On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>for all transparent hugepage page faults by default, not only in
>MADV_HUGEPAGE regions.
>
>Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>---
> mm/huge_memory.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
>diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>index a92012a..abf047e 100644
>--- a/mm/huge_memory.c
>+++ b/mm/huge_memory.c
>@@ -28,10 +28,8 @@
>
> /*
>  * By default transparent hugepage support is enabled for all mappings

This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
order that avoid to risk increase the memory footprint of applications w/o a 
guaranteed benefit.

Regards,
Wanpeng Li 

>- * and khugepaged scans all mappings. Defrag is only invoked by
>- * khugepaged hugepage allocations and by page faults inside
>- * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>- * allocations.
>+ * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>+ * hugepage allocations and by page faults for all hugepage allocations.
>  */
> unsigned long transparent_hugepage_flags __read_mostly =
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>-- 
>1.8.1.2
>
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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Jianguo Wu]

Hi Wanpeng,

On 2013/9/5 10:11, Wanpeng Li wrote:

> Hi Jianguo,
> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>> for all transparent hugepage page faults by default, not only in
>> MADV_HUGEPAGE regions.
>>
>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>> ---
>> mm/huge_memory.c | 6 ++----
>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>> index a92012a..abf047e 100644
>> --- a/mm/huge_memory.c
>> +++ b/mm/huge_memory.c
>> @@ -28,10 +28,8 @@
>>
>> /*
>>  * By default transparent hugepage support is enabled for all mappings
> 
> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
> order that avoid to risk increase the memory footprint of applications w/o a 
> guaranteed benefit.
> 

Right, how about this:

By default transparent hugepage support is disabled in order that avoid to risk
increase the memory footprint of applications w/o a guaranteed benefit, and
khugepaged scans all mappings when transparent hugepage enabled.
Defrag is invoked by khugepaged hugepage allocations and by page faults for all
hugepage allocations.

Thanks,
Jianguo Wu

> Regards,
> Wanpeng Li 
> 
>> - * and khugepaged scans all mappings. Defrag is only invoked by
>> - * khugepaged hugepage allocations and by page faults inside
>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>> - * allocations.
>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>> + * hugepage allocations and by page faults for all hugepage allocations.
>>  */
>> unsigned long transparent_hugepage_flags __read_mostly =
>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>> -- 
>> 1.8.1.2
>>
>> --
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>> the body to majordomo@kvack.org.  For more info on Linux MM,
>> see: http://www.linux-mm.org/ .
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> 
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> 



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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>Hi Wanpeng,
>
>On 2013/9/5 10:11, Wanpeng Li wrote:
>
>> Hi Jianguo,
>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>> for all transparent hugepage page faults by default, not only in
>>> MADV_HUGEPAGE regions.
>>>
>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>> ---
>>> mm/huge_memory.c | 6 ++----
>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>> index a92012a..abf047e 100644
>>> --- a/mm/huge_memory.c
>>> +++ b/mm/huge_memory.c
>>> @@ -28,10 +28,8 @@
>>>
>>> /*
>>>  * By default transparent hugepage support is enabled for all mappings
>> 
>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>> order that avoid to risk increase the memory footprint of applications w/o a 
>> guaranteed benefit.
>> 
>
>Right, how about this:
>
>By default transparent hugepage support is disabled in order that avoid to risk

I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
by default.

Regards,
Wanpeng Li 

>increase the memory footprint of applications w/o a guaranteed benefit, and
>khugepaged scans all mappings when transparent hugepage enabled.
>Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>hugepage allocations.
>
>Thanks,
>Jianguo Wu
>
>> Regards,
>> Wanpeng Li 
>> 
>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>> - * khugepaged hugepage allocations and by page faults inside
>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>> - * allocations.
>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>  */
>>> unsigned long transparent_hugepage_flags __read_mostly =
>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>> -- 
>>> 1.8.1.2
>>>
>>> --
>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
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>>> see: http://www.linux-mm.org/ .
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>> 
>> --
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>> 
>> 
>
>

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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>Hi Wanpeng,
>
>On 2013/9/5 10:11, Wanpeng Li wrote:
>
>> Hi Jianguo,
>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>> for all transparent hugepage page faults by default, not only in
>>> MADV_HUGEPAGE regions.
>>>
>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>> ---
>>> mm/huge_memory.c | 6 ++----
>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>> index a92012a..abf047e 100644
>>> --- a/mm/huge_memory.c
>>> +++ b/mm/huge_memory.c
>>> @@ -28,10 +28,8 @@
>>>
>>> /*
>>>  * By default transparent hugepage support is enabled for all mappings
>> 
>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>> order that avoid to risk increase the memory footprint of applications w/o a 
>> guaranteed benefit.
>> 
>
>Right, how about this:
>
>By default transparent hugepage support is disabled in order that avoid to risk

I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
by default.

Regards,
Wanpeng Li 

>increase the memory footprint of applications w/o a guaranteed benefit, and
>khugepaged scans all mappings when transparent hugepage enabled.
>Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>hugepage allocations.
>
>Thanks,
>Jianguo Wu
>
>> Regards,
>> Wanpeng Li 
>> 
>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>> - * khugepaged hugepage allocations and by page faults inside
>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>> - * allocations.
>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>  */
>>> unsigned long transparent_hugepage_flags __read_mostly =
>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>> -- 
>>> 1.8.1.2
>>>
>>> --
>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>> see: http://www.linux-mm.org/ .
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>> 
>> --
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>> 
>> 
>
>

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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Jianguo Wu]

On 2013/9/5 11:37, Wanpeng Li wrote:

> On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>> Hi Wanpeng,
>>
>> On 2013/9/5 10:11, Wanpeng Li wrote:
>>
>>> Hi Jianguo,
>>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>>> for all transparent hugepage page faults by default, not only in
>>>> MADV_HUGEPAGE regions.
>>>>
>>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>>> ---
>>>> mm/huge_memory.c | 6 ++----
>>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>>> index a92012a..abf047e 100644
>>>> --- a/mm/huge_memory.c
>>>> +++ b/mm/huge_memory.c
>>>> @@ -28,10 +28,8 @@
>>>>
>>>> /*
>>>>  * By default transparent hugepage support is enabled for all mappings
>>>
>>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>>> order that avoid to risk increase the memory footprint of applications w/o a 
>>> guaranteed benefit.
>>>
>>
>> Right, how about this:
>>
>> By default transparent hugepage support is disabled in order that avoid to risk
> 
> I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
> by default.
> 

Hi Wanpeng,

We have TRANSPARENT_HUGEPAGE and TRANSPARENT_HUGEPAGE_ALWAYS/TRANSPARENT_HUGEPAGE_MADVISE,
TRANSPARENT_HUGEPAGE_ALWAYS or TRANSPARENT_HUGEPAGE_MADVISE is configured only if TRANSPARENT_HUGEPAGE
is configured.

By default, TRANSPARENT_HUGEPAGE=n, and TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.

commit 13ece886d9(thp: transparent hugepage config choice):

 config TRANSPARENT_HUGEPAGE
-       bool "Transparent Hugepage Support" if EMBEDDED
+       bool "Transparent Hugepage Support"
        depends on X86 && MMU
-       default y

+choice
+       prompt "Transparent Hugepage Support sysfs defaults"
+       depends on TRANSPARENT_HUGEPAGE
+       default TRANSPARENT_HUGEPAGE_ALWAYS

Thanks,
Jianguo Wu

> Regards,
> Wanpeng Li 
> 
>> increase the memory footprint of applications w/o a guaranteed benefit, and
>> khugepaged scans all mappings when transparent hugepage enabled.
>> Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>> hugepage allocations.
>>
>> Thanks,
>> Jianguo Wu
>>
>>> Regards,
>>> Wanpeng Li 
>>>
>>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>>> - * khugepaged hugepage allocations and by page faults inside
>>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>>> - * allocations.
>>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>>  */
>>>> unsigned long transparent_hugepage_flags __read_mostly =
>>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>>> -- 
>>>> 1.8.1.2
>>>>
>>>> --
>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>> see: http://www.linux-mm.org/ .
>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>
>>> --
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>>>
>>>
>>
>>
> 
> 
> .
> 



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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

Hi Jianguo,
On Thu, Sep 05, 2013 at 11:54:00AM +0800, Jianguo Wu wrote:
>On 2013/9/5 11:37, Wanpeng Li wrote:
>
>> On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>>> Hi Wanpeng,
>>>
>>> On 2013/9/5 10:11, Wanpeng Li wrote:
>>>
>>>> Hi Jianguo,
>>>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>>>> for all transparent hugepage page faults by default, not only in
>>>>> MADV_HUGEPAGE regions.
>>>>>
>>>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>>>> ---
>>>>> mm/huge_memory.c | 6 ++----
>>>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>>>> index a92012a..abf047e 100644
>>>>> --- a/mm/huge_memory.c
>>>>> +++ b/mm/huge_memory.c
>>>>> @@ -28,10 +28,8 @@
>>>>>
>>>>> /*
>>>>>  * By default transparent hugepage support is enabled for all mappings
>>>>
>>>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>>>> order that avoid to risk increase the memory footprint of applications w/o a 
>>>> guaranteed benefit.
>>>>
>>>
>>> Right, how about this:
>>>
>>> By default transparent hugepage support is disabled in order that avoid to risk
>> 
>> I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
>> by default.
>> 
>
>Hi Wanpeng,
>
>We have TRANSPARENT_HUGEPAGE and TRANSPARENT_HUGEPAGE_ALWAYS/TRANSPARENT_HUGEPAGE_MADVISE,
>TRANSPARENT_HUGEPAGE_ALWAYS or TRANSPARENT_HUGEPAGE_MADVISE is configured only if TRANSPARENT_HUGEPAGE
>is configured.
>
>By default, TRANSPARENT_HUGEPAGE=n, and TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.
>
>commit 13ece886d9(thp: transparent hugepage config choice):
>
> config TRANSPARENT_HUGEPAGE
>-       bool "Transparent Hugepage Support" if EMBEDDED
>+       bool "Transparent Hugepage Support"
>        depends on X86 && MMU
>-       default y
>
>+choice
>+       prompt "Transparent Hugepage Support sysfs defaults"
>+       depends on TRANSPARENT_HUGEPAGE
>+       default TRANSPARENT_HUGEPAGE_ALWAYS
>

mmotm tree:

grep 'TRANSPARENT_HUGEPAGE' .config
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
CONFIG_TRANSPARENT_HUGEPAGE=y
# CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y

distro:

grep 'TRANSPARENT_HUGEPAGE' config-3.8.0-26-generic 
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
CONFIG_TRANSPARENT_HUGEPAGE=y
# CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y


>Thanks,
>Jianguo Wu
>
>> Regards,
>> Wanpeng Li 
>> 
>>> increase the memory footprint of applications w/o a guaranteed benefit, and
>>> khugepaged scans all mappings when transparent hugepage enabled.
>>> Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>>> hugepage allocations.
>>>
>>> Thanks,
>>> Jianguo Wu
>>>
>>>> Regards,
>>>> Wanpeng Li 
>>>>
>>>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>>>> - * khugepaged hugepage allocations and by page faults inside
>>>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>>>> - * allocations.
>>>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>>>  */
>>>>> unsigned long transparent_hugepage_flags __read_mostly =
>>>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>>>> -- 
>>>>> 1.8.1.2
>>>>>
>>>>> --
>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>> see: http://www.linux-mm.org/ .
>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>
>>>> --
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>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>> see: http://www.linux-mm.org/ .
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>>>>
>>>>
>>>
>>>
>> 
>> 
>> .
>> 
>
>

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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

Hi Jianguo,
On Thu, Sep 05, 2013 at 11:54:00AM +0800, Jianguo Wu wrote:
>On 2013/9/5 11:37, Wanpeng Li wrote:
>
>> On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>>> Hi Wanpeng,
>>>
>>> On 2013/9/5 10:11, Wanpeng Li wrote:
>>>
>>>> Hi Jianguo,
>>>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>>>> for all transparent hugepage page faults by default, not only in
>>>>> MADV_HUGEPAGE regions.
>>>>>
>>>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>>>> ---
>>>>> mm/huge_memory.c | 6 ++----
>>>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>>>> index a92012a..abf047e 100644
>>>>> --- a/mm/huge_memory.c
>>>>> +++ b/mm/huge_memory.c
>>>>> @@ -28,10 +28,8 @@
>>>>>
>>>>> /*
>>>>>  * By default transparent hugepage support is enabled for all mappings
>>>>
>>>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>>>> order that avoid to risk increase the memory footprint of applications w/o a 
>>>> guaranteed benefit.
>>>>
>>>
>>> Right, how about this:
>>>
>>> By default transparent hugepage support is disabled in order that avoid to risk
>> 
>> I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
>> by default.
>> 
>
>Hi Wanpeng,
>
>We have TRANSPARENT_HUGEPAGE and TRANSPARENT_HUGEPAGE_ALWAYS/TRANSPARENT_HUGEPAGE_MADVISE,
>TRANSPARENT_HUGEPAGE_ALWAYS or TRANSPARENT_HUGEPAGE_MADVISE is configured only if TRANSPARENT_HUGEPAGE
>is configured.
>
>By default, TRANSPARENT_HUGEPAGE=n, and TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.
>
>commit 13ece886d9(thp: transparent hugepage config choice):
>
> config TRANSPARENT_HUGEPAGE
>-       bool "Transparent Hugepage Support" if EMBEDDED
>+       bool "Transparent Hugepage Support"
>        depends on X86 && MMU
>-       default y
>
>+choice
>+       prompt "Transparent Hugepage Support sysfs defaults"
>+       depends on TRANSPARENT_HUGEPAGE
>+       default TRANSPARENT_HUGEPAGE_ALWAYS
>

mmotm tree:

grep 'TRANSPARENT_HUGEPAGE' .config
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
CONFIG_TRANSPARENT_HUGEPAGE=y
# CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y

distro:

grep 'TRANSPARENT_HUGEPAGE' config-3.8.0-26-generic 
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
CONFIG_TRANSPARENT_HUGEPAGE=y
# CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y


>Thanks,
>Jianguo Wu
>
>> Regards,
>> Wanpeng Li 
>> 
>>> increase the memory footprint of applications w/o a guaranteed benefit, and
>>> khugepaged scans all mappings when transparent hugepage enabled.
>>> Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>>> hugepage allocations.
>>>
>>> Thanks,
>>> Jianguo Wu
>>>
>>>> Regards,
>>>> Wanpeng Li 
>>>>
>>>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>>>> - * khugepaged hugepage allocations and by page faults inside
>>>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>>>> - * allocations.
>>>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>>>  */
>>>>> unsigned long transparent_hugepage_flags __read_mostly =
>>>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>>>> -- 
>>>>> 1.8.1.2
>>>>>
>>>>> --
>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>> see: http://www.linux-mm.org/ .
>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>
>>>> --
>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>> see: http://www.linux-mm.org/ .
>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>
>>>>
>>>
>>>
>> 
>> 
>> .
>> 
>
>

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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Jianguo Wu]

On 2013/9/5 12:58, Wanpeng Li wrote:

> Hi Jianguo,
> On Thu, Sep 05, 2013 at 11:54:00AM +0800, Jianguo Wu wrote:
>> On 2013/9/5 11:37, Wanpeng Li wrote:
>>
>>> On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>>>> Hi Wanpeng,
>>>>
>>>> On 2013/9/5 10:11, Wanpeng Li wrote:
>>>>
>>>>> Hi Jianguo,
>>>>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>>>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>>>>> for all transparent hugepage page faults by default, not only in
>>>>>> MADV_HUGEPAGE regions.
>>>>>>
>>>>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>>>>> ---
>>>>>> mm/huge_memory.c | 6 ++----
>>>>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>>
>>>>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>>>>> index a92012a..abf047e 100644
>>>>>> --- a/mm/huge_memory.c
>>>>>> +++ b/mm/huge_memory.c
>>>>>> @@ -28,10 +28,8 @@
>>>>>>
>>>>>> /*
>>>>>>  * By default transparent hugepage support is enabled for all mappings
>>>>>
>>>>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>>>>> order that avoid to risk increase the memory footprint of applications w/o a 
>>>>> guaranteed benefit.
>>>>>
>>>>
>>>> Right, how about this:
>>>>
>>>> By default transparent hugepage support is disabled in order that avoid to risk
>>>
>>> I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
>>> by default.
>>>
>>
>> Hi Wanpeng,
>>
>> We have TRANSPARENT_HUGEPAGE and TRANSPARENT_HUGEPAGE_ALWAYS/TRANSPARENT_HUGEPAGE_MADVISE,
>> TRANSPARENT_HUGEPAGE_ALWAYS or TRANSPARENT_HUGEPAGE_MADVISE is configured only if TRANSPARENT_HUGEPAGE
>> is configured.
>>
>> By default, TRANSPARENT_HUGEPAGE=n, and TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.
>>
>> commit 13ece886d9(thp: transparent hugepage config choice):
>>
>> config TRANSPARENT_HUGEPAGE
>> -       bool "Transparent Hugepage Support" if EMBEDDED
>> +       bool "Transparent Hugepage Support"
>>        depends on X86 && MMU
>> -       default y
>>
>> +choice
>> +       prompt "Transparent Hugepage Support sysfs defaults"
>> +       depends on TRANSPARENT_HUGEPAGE
>> +       default TRANSPARENT_HUGEPAGE_ALWAYS
>>
> 
> mmotm tree:
> 
> grep 'TRANSPARENT_HUGEPAGE' .config
> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
> CONFIG_TRANSPARENT_HUGEPAGE=y
> # CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
> CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y
> 
> distro:
> 
> grep 'TRANSPARENT_HUGEPAGE' config-3.8.0-26-generic 
> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
> CONFIG_TRANSPARENT_HUGEPAGE=y
> # CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
> CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y
> 

Hi Wanpeng,

I'm a little confused, at mm/Kconfig, TRANSPARENT_HUGEPAGE is not configured by default.

and in x86_64, linus tree:

$make defconfig
$grep 'TRANSPARENT_HUGEPAGE' .config
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
# CONFIG_TRANSPARENT_HUGEPAGE is not set

Do i misunderstand something herei 1/4 ?

Thanks

> 
>> Thanks,
>> Jianguo Wu
>>
>>> Regards,
>>> Wanpeng Li 
>>>
>>>> increase the memory footprint of applications w/o a guaranteed benefit, and
>>>> khugepaged scans all mappings when transparent hugepage enabled.
>>>> Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>>>> hugepage allocations.
>>>>
>>>> Thanks,
>>>> Jianguo Wu
>>>>
>>>>> Regards,
>>>>> Wanpeng Li 
>>>>>
>>>>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>>>>> - * khugepaged hugepage allocations and by page faults inside
>>>>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>>>>> - * allocations.
>>>>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>>>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>>>>  */
>>>>>> unsigned long transparent_hugepage_flags __read_mostly =
>>>>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>>>>> -- 
>>>>>> 1.8.1.2
>>>>>>
>>>>>> --
>>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>>> see: http://www.linux-mm.org/ .
>>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>>
>>>>> --
>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>> see: http://www.linux-mm.org/ .
>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>> .
>>>
>>
>>
> 
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@kvack.org.  For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
> 
> 



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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

Hi Jianguo,
On Thu, Sep 05, 2013 at 02:34:12PM +0800, Jianguo Wu wrote:
>On 2013/9/5 12:58, Wanpeng Li wrote:
>
>> Hi Jianguo,
>> On Thu, Sep 05, 2013 at 11:54:00AM +0800, Jianguo Wu wrote:
>>> On 2013/9/5 11:37, Wanpeng Li wrote:
>>>
>>>> On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>>>>> Hi Wanpeng,
>>>>>
>>>>> On 2013/9/5 10:11, Wanpeng Li wrote:
>>>>>
>>>>>> Hi Jianguo,
>>>>>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>>>>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>>>>>> for all transparent hugepage page faults by default, not only in
>>>>>>> MADV_HUGEPAGE regions.
>>>>>>>
>>>>>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>>>>>> ---
>>>>>>> mm/huge_memory.c | 6 ++----
>>>>>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>>>
>>>>>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>>>>>> index a92012a..abf047e 100644
>>>>>>> --- a/mm/huge_memory.c
>>>>>>> +++ b/mm/huge_memory.c
>>>>>>> @@ -28,10 +28,8 @@
>>>>>>>
>>>>>>> /*
>>>>>>>  * By default transparent hugepage support is enabled for all mappings
>>>>>>
>>>>>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>>>>>> order that avoid to risk increase the memory footprint of applications w/o a 
>>>>>> guaranteed benefit.
>>>>>>
>>>>>
>>>>> Right, how about this:
>>>>>
>>>>> By default transparent hugepage support is disabled in order that avoid to risk
>>>>
>>>> I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
>>>> by default.
>>>>
>>>
>>> Hi Wanpeng,
>>>
>>> We have TRANSPARENT_HUGEPAGE and TRANSPARENT_HUGEPAGE_ALWAYS/TRANSPARENT_HUGEPAGE_MADVISE,
>>> TRANSPARENT_HUGEPAGE_ALWAYS or TRANSPARENT_HUGEPAGE_MADVISE is configured only if TRANSPARENT_HUGEPAGE
>>> is configured.
>>>
>>> By default, TRANSPARENT_HUGEPAGE=n, and TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.
>>>
>>> commit 13ece886d9(thp: transparent hugepage config choice):
>>>
>>> config TRANSPARENT_HUGEPAGE
>>> -       bool "Transparent Hugepage Support" if EMBEDDED
>>> +       bool "Transparent Hugepage Support"
>>>        depends on X86 && MMU
>>> -       default y
>>>
>>> +choice
>>> +       prompt "Transparent Hugepage Support sysfs defaults"
>>> +       depends on TRANSPARENT_HUGEPAGE
>>> +       default TRANSPARENT_HUGEPAGE_ALWAYS
>>>
>> 
>> mmotm tree:
>> 
>> grep 'TRANSPARENT_HUGEPAGE' .config
>> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
>> CONFIG_TRANSPARENT_HUGEPAGE=y
>> # CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
>> CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y
>> 
>> distro:
>> 
>> grep 'TRANSPARENT_HUGEPAGE' config-3.8.0-26-generic 
>> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
>> CONFIG_TRANSPARENT_HUGEPAGE=y
>> # CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
>> CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y
>> 
>
>Hi Wanpeng,
>
>I'm a little confused, at mm/Kconfig, TRANSPARENT_HUGEPAGE is not configured by default.
>
>and in x86_64, linus tree:
>
>$make defconfig
>$grep 'TRANSPARENT_HUGEPAGE' .config
>CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
># CONFIG_TRANSPARENT_HUGEPAGE is not set
>

Ah, ok, maybe distro enable them.

Regards,
Wanpeng Li 

>Do i misunderstand something herei 1/4 ?
>
>Thanks
>
>> 
>>> Thanks,
>>> Jianguo Wu
>>>
>>>> Regards,
>>>> Wanpeng Li 
>>>>
>>>>> increase the memory footprint of applications w/o a guaranteed benefit, and
>>>>> khugepaged scans all mappings when transparent hugepage enabled.
>>>>> Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>>>>> hugepage allocations.
>>>>>
>>>>> Thanks,
>>>>> Jianguo Wu
>>>>>
>>>>>> Regards,
>>>>>> Wanpeng Li 
>>>>>>
>>>>>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>>>>>> - * khugepaged hugepage allocations and by page faults inside
>>>>>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>>>>>> - * allocations.
>>>>>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>>>>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>>>>>  */
>>>>>>> unsigned long transparent_hugepage_flags __read_mostly =
>>>>>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>>>>>> -- 
>>>>>>> 1.8.1.2
>>>>>>>
>>>>>>> --
>>>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>>>> see: http://www.linux-mm.org/ .
>>>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>>>
>>>>>> --
>>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>>> see: http://www.linux-mm.org/ .
>>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>> .
>>>>
>>>
>>>
>> 
>> --
>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>> the body to majordomo@kvack.org.  For more info on Linux MM,
>> see: http://www.linux-mm.org/ .
>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>> 
>> 
>
>

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Re: [PATCH] mm/thp: fix comments in transparent_hugepage_flags

[Wanpeng Li]

Hi Jianguo,
On Thu, Sep 05, 2013 at 02:34:12PM +0800, Jianguo Wu wrote:
>On 2013/9/5 12:58, Wanpeng Li wrote:
>
>> Hi Jianguo,
>> On Thu, Sep 05, 2013 at 11:54:00AM +0800, Jianguo Wu wrote:
>>> On 2013/9/5 11:37, Wanpeng Li wrote:
>>>
>>>> On Thu, Sep 05, 2013 at 11:04:22AM +0800, Jianguo Wu wrote:
>>>>> Hi Wanpeng,
>>>>>
>>>>> On 2013/9/5 10:11, Wanpeng Li wrote:
>>>>>
>>>>>> Hi Jianguo,
>>>>>> On Wed, Sep 04, 2013 at 09:30:22PM +0800, Jianguo Wu wrote:
>>>>>>> Since commit d39d33c332(thp: enable direct defrag), defrag is enable
>>>>>>> for all transparent hugepage page faults by default, not only in
>>>>>>> MADV_HUGEPAGE regions.
>>>>>>>
>>>>>>> Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
>>>>>>> ---
>>>>>>> mm/huge_memory.c | 6 ++----
>>>>>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>>>
>>>>>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>>>>>> index a92012a..abf047e 100644
>>>>>>> --- a/mm/huge_memory.c
>>>>>>> +++ b/mm/huge_memory.c
>>>>>>> @@ -28,10 +28,8 @@
>>>>>>>
>>>>>>> /*
>>>>>>>  * By default transparent hugepage support is enabled for all mappings
>>>>>>
>>>>>> This is also stale. TRANSPARENT_HUGEPAGE_ALWAYS is not configured by default in
>>>>>> order that avoid to risk increase the memory footprint of applications w/o a 
>>>>>> guaranteed benefit.
>>>>>>
>>>>>
>>>>> Right, how about this:
>>>>>
>>>>> By default transparent hugepage support is disabled in order that avoid to risk
>>>>
>>>> I don't think it's disabled. TRANSPARENT_HUGEPAGE_MADVISE is configured
>>>> by default.
>>>>
>>>
>>> Hi Wanpeng,
>>>
>>> We have TRANSPARENT_HUGEPAGE and TRANSPARENT_HUGEPAGE_ALWAYS/TRANSPARENT_HUGEPAGE_MADVISE,
>>> TRANSPARENT_HUGEPAGE_ALWAYS or TRANSPARENT_HUGEPAGE_MADVISE is configured only if TRANSPARENT_HUGEPAGE
>>> is configured.
>>>
>>> By default, TRANSPARENT_HUGEPAGE=n, and TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.
>>>
>>> commit 13ece886d9(thp: transparent hugepage config choice):
>>>
>>> config TRANSPARENT_HUGEPAGE
>>> -       bool "Transparent Hugepage Support" if EMBEDDED
>>> +       bool "Transparent Hugepage Support"
>>>        depends on X86 && MMU
>>> -       default y
>>>
>>> +choice
>>> +       prompt "Transparent Hugepage Support sysfs defaults"
>>> +       depends on TRANSPARENT_HUGEPAGE
>>> +       default TRANSPARENT_HUGEPAGE_ALWAYS
>>>
>> 
>> mmotm tree:
>> 
>> grep 'TRANSPARENT_HUGEPAGE' .config
>> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
>> CONFIG_TRANSPARENT_HUGEPAGE=y
>> # CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
>> CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y
>> 
>> distro:
>> 
>> grep 'TRANSPARENT_HUGEPAGE' config-3.8.0-26-generic 
>> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
>> CONFIG_TRANSPARENT_HUGEPAGE=y
>> # CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS is not set
>> CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y
>> 
>
>Hi Wanpeng,
>
>I'm a little confused, at mm/Kconfig, TRANSPARENT_HUGEPAGE is not configured by default.
>
>and in x86_64, linus tree:
>
>$make defconfig
>$grep 'TRANSPARENT_HUGEPAGE' .config
>CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
># CONFIG_TRANSPARENT_HUGEPAGE is not set
>

Ah, ok, maybe distro enable them.

Regards,
Wanpeng Li 

>Do i misunderstand something here？
>
>Thanks
>
>> 
>>> Thanks,
>>> Jianguo Wu
>>>
>>>> Regards,
>>>> Wanpeng Li 
>>>>
>>>>> increase the memory footprint of applications w/o a guaranteed benefit, and
>>>>> khugepaged scans all mappings when transparent hugepage enabled.
>>>>> Defrag is invoked by khugepaged hugepage allocations and by page faults for all
>>>>> hugepage allocations.
>>>>>
>>>>> Thanks,
>>>>> Jianguo Wu
>>>>>
>>>>>> Regards,
>>>>>> Wanpeng Li 
>>>>>>
>>>>>>> - * and khugepaged scans all mappings. Defrag is only invoked by
>>>>>>> - * khugepaged hugepage allocations and by page faults inside
>>>>>>> - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived
>>>>>>> - * allocations.
>>>>>>> + * and khugepaged scans all mappings. Defrag is invoked by khugepaged
>>>>>>> + * hugepage allocations and by page faults for all hugepage allocations.
>>>>>>>  */
>>>>>>> unsigned long transparent_hugepage_flags __read_mostly =
>>>>>>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS
>>>>>>> -- 
>>>>>>> 1.8.1.2
>>>>>>>
>>>>>>> --
>>>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>>>> see: http://www.linux-mm.org/ .
>>>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>>>
>>>>>> --
>>>>>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>>>>>> the body to majordomo@kvack.org.  For more info on Linux MM,
>>>>>> see: http://www.linux-mm.org/ .
>>>>>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>> .
>>>>
>>>
>>>
>> 
>> --
>> To unsubscribe, send a message with 'unsubscribe linux-mm' in
>> the body to majordomo@kvack.org.  For more info on Linux MM,
>> see: http://www.linux-mm.org/ .
>> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
>> 
>> 
>
>

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