Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-30 Thread Sergey Senozhatsky
On (08/29/16 14:31), Aaron Lu wrote: > > The global zero page is used to satisfy an anonymous read fault. If > THP(Transparent HugePage) is enabled then the global huge zero page is used. > The global huge zero page uses an atomic counter for reference counting > and is allocated/freed

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-30 Thread Sergey Senozhatsky
On (08/29/16 14:31), Aaron Lu wrote: > > The global zero page is used to satisfy an anonymous read fault. If > THP(Transparent HugePage) is enabled then the global huge zero page is used. > The global huge zero page uses an atomic counter for reference counting > and is allocated/freed

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-30 Thread Anshuman Khandual
On 08/30/2016 11:24 AM, Aaron Lu wrote: > On 08/30/2016 12:44 PM, Anshuman Khandual wrote: >> > On 08/30/2016 09:09 AM, Andrew Morton wrote: >>> >> On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: >>> >> >> > Case used for test on Haswell EP: >> > usemem -n

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-30 Thread Anshuman Khandual
On 08/30/2016 11:24 AM, Aaron Lu wrote: > On 08/30/2016 12:44 PM, Anshuman Khandual wrote: >> > On 08/30/2016 09:09 AM, Andrew Morton wrote: >>> >> On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: >>> >> >> > Case used for test on Haswell EP: >> > usemem -n 72 --readonly -j

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/30/2016 12:44 PM, Anshuman Khandual wrote: > On 08/30/2016 09:09 AM, Andrew Morton wrote: >> On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: >> > Case used for test on Haswell EP: > usemem -n 72 --readonly -j 0x20 100G > Which spawns 72 processes and

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/30/2016 12:44 PM, Anshuman Khandual wrote: > On 08/30/2016 09:09 AM, Andrew Morton wrote: >> On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: >> > Case used for test on Haswell EP: > usemem -n 72 --readonly -j 0x20 100G > Which spawns 72 processes and each will mmap 100G

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/30/2016 11:39 AM, Andrew Morton wrote: > On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > Case used for test on Haswell EP: usemem -n 72 --readonly -j 0x20 100G Which spawns 72 processes and each will mmap 100G anonymous space and then do

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/30/2016 11:39 AM, Andrew Morton wrote: > On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > Case used for test on Haswell EP: usemem -n 72 --readonly -j 0x20 100G Which spawns 72 processes and each will mmap 100G anonymous space and then do read only access to

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Tue, 30 Aug 2016 10:44:21 +0530 Anshuman Khandual wrote: > On 08/30/2016 04:20 AM, Andrew Morton wrote: > > On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > > > >> > > >> > The global zero page is used to satisfy an anonymous read

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Tue, 30 Aug 2016 10:44:21 +0530 Anshuman Khandual wrote: > On 08/30/2016 04:20 AM, Andrew Morton wrote: > > On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > > > >> > > >> > The global zero page is used to satisfy an anonymous read fault. If > >> > THP(Transparent HugePage) is enabled

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/30/2016 04:20 AM, Andrew Morton wrote: > On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > >> > >> > The global zero page is used to satisfy an anonymous read fault. If >> > THP(Transparent HugePage) is enabled then the global huge zero page is >> > used. >> > The

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/30/2016 04:20 AM, Andrew Morton wrote: > On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > >> > >> > The global zero page is used to satisfy an anonymous read fault. If >> > THP(Transparent HugePage) is enabled then the global huge zero page is >> > used. >> > The global huge zero

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Tue, 30 Aug 2016 10:14:25 +0530 Anshuman Khandual wrote: > On 08/30/2016 09:09 AM, Andrew Morton wrote: > > On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > > > Case used for test on Haswell EP: > usemem -n 72 --readonly -j

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Tue, 30 Aug 2016 10:14:25 +0530 Anshuman Khandual wrote: > On 08/30/2016 09:09 AM, Andrew Morton wrote: > > On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > > > Case used for test on Haswell EP: > usemem -n 72 --readonly -j 0x20 100G > Which spawns 72 processes and

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/30/2016 09:09 AM, Andrew Morton wrote: > On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > Case used for test on Haswell EP: usemem -n 72 --readonly -j 0x20 100G Which spawns 72 processes and each will mmap 100G anonymous space and then do

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/30/2016 09:09 AM, Andrew Morton wrote: > On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > Case used for test on Haswell EP: usemem -n 72 --readonly -j 0x20 100G Which spawns 72 processes and each will mmap 100G anonymous space and then do read only access to

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > >> Case used for test on Haswell EP: > >> usemem -n 72 --readonly -j 0x20 100G > >> Which spawns 72 processes and each will mmap 100G anonymous space and > >> then do read only access to that space sequentially with a

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Tue, 30 Aug 2016 11:09:15 +0800 Aaron Lu wrote: > >> Case used for test on Haswell EP: > >> usemem -n 72 --readonly -j 0x20 100G > >> Which spawns 72 processes and each will mmap 100G anonymous space and > >> then do read only access to that space sequentially with a step of 2MB. > >> >

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/30/2016 06:50 AM, Andrew Morton wrote: > On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > >> >> The global zero page is used to satisfy an anonymous read fault. If >> THP(Transparent HugePage) is enabled then the global huge zero page is used. >> The global huge

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/30/2016 06:50 AM, Andrew Morton wrote: > On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > >> >> The global zero page is used to satisfy an anonymous read fault. If >> THP(Transparent HugePage) is enabled then the global huge zero page is used. >> The global huge zero page uses an

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > > The global zero page is used to satisfy an anonymous read fault. If > THP(Transparent HugePage) is enabled then the global huge zero page is used. > The global huge zero page uses an atomic counter for reference counting

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Andrew Morton
On Mon, 29 Aug 2016 14:31:20 +0800 Aaron Lu wrote: > > The global zero page is used to satisfy an anonymous read fault. If > THP(Transparent HugePage) is enabled then the global huge zero page is used. > The global huge zero page uses an atomic counter for reference counting > and is

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On Mon, Aug 29, 2016 at 07:17:58PM +0530, Anshuman Khandual wrote: > On 08/29/2016 02:23 PM, Aaron Lu wrote: > > On 08/29/2016 04:49 PM, Anshuman Khandual wrote: > >> > On 08/29/2016 12:01 PM, Aaron Lu wrote: > >>> >> The global zero page is used to satisfy an anonymous read fault. If > >>> >>

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On Mon, Aug 29, 2016 at 07:17:58PM +0530, Anshuman Khandual wrote: > On 08/29/2016 02:23 PM, Aaron Lu wrote: > > On 08/29/2016 04:49 PM, Anshuman Khandual wrote: > >> > On 08/29/2016 12:01 PM, Aaron Lu wrote: > >>> >> The global zero page is used to satisfy an anonymous read fault. If > >>> >>

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/29/2016 02:23 PM, Aaron Lu wrote: > On 08/29/2016 04:49 PM, Anshuman Khandual wrote: >> > On 08/29/2016 12:01 PM, Aaron Lu wrote: >>> >> The global zero page is used to satisfy an anonymous read fault. If >>> >> THP(Transparent HugePage) is enabled then the global huge zero page is >>> >>

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/29/2016 02:23 PM, Aaron Lu wrote: > On 08/29/2016 04:49 PM, Anshuman Khandual wrote: >> > On 08/29/2016 12:01 PM, Aaron Lu wrote: >>> >> The global zero page is used to satisfy an anonymous read fault. If >>> >> THP(Transparent HugePage) is enabled then the global huge zero page is >>> >>

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/29/2016 04:49 PM, Anshuman Khandual wrote: > On 08/29/2016 12:01 PM, Aaron Lu wrote: >> The global zero page is used to satisfy an anonymous read fault. If >> THP(Transparent HugePage) is enabled then the global huge zero page is used. >> The global huge zero page uses an atomic counter for

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
On 08/29/2016 04:49 PM, Anshuman Khandual wrote: > On 08/29/2016 12:01 PM, Aaron Lu wrote: >> The global zero page is used to satisfy an anonymous read fault. If >> THP(Transparent HugePage) is enabled then the global huge zero page is used. >> The global huge zero page uses an atomic counter for

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/29/2016 12:01 PM, Aaron Lu wrote: > The global zero page is used to satisfy an anonymous read fault. If > THP(Transparent HugePage) is enabled then the global huge zero page is used. > The global huge zero page uses an atomic counter for reference counting > and is allocated/freed

Re: [PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Anshuman Khandual
On 08/29/2016 12:01 PM, Aaron Lu wrote: > The global zero page is used to satisfy an anonymous read fault. If > THP(Transparent HugePage) is enabled then the global huge zero page is used. > The global huge zero page uses an atomic counter for reference counting > and is allocated/freed

[PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
The global zero page is used to satisfy an anonymous read fault. If THP(Transparent HugePage) is enabled then the global huge zero page is used. The global huge zero page uses an atomic counter for reference counting and is allocated/freed dynamically according to its counter value. CPU time

[PATCH] thp: reduce usage of huge zero page's atomic counter

2016-08-29 Thread Aaron Lu
The global zero page is used to satisfy an anonymous read fault. If THP(Transparent HugePage) is enabled then the global huge zero page is used. The global huge zero page uses an atomic counter for reference counting and is allocated/freed dynamically according to its counter value. CPU time