On Mon, Mar 28, 2011 at 4:17 PM, Minchan Kim <minchan.kim@xxxxxxxxx> wrote:
> On Mon, Mar 28, 2011 at 12:26 PM, Ying Han <yinghan@xxxxxxxxxx> wrote:
>> Two new stats in per-memcg memory.stat which tracks the number of
>> page faults and number of major page faults.
>>
>> "pgfault"
>> "pgmajfault"
>>
>> They are different from "pgpgin"/"pgpgout" stat which count number of
>> pages charged/discharged to the cgroup and have no meaning of reading/
>> writing page to disk.
>>
>> It is valuable to track the two stats for both measuring application's
>> performance as well as the efficiency of the kernel page reclaim path.
>> Counting pagefaults per process is useful, but we also need the aggregated
>> value since processes are monitored and controlled in cgroup basis in memcg.
>>
>> Functional test: check the total number of pgfault/pgmajfault of all
>> memcgs and compare with global vmstat value:
>>
>> $ cat /proc/vmstat | grep fault
>> pgfault 1070751
>> pgmajfault 553
>>
>> $ cat /dev/cgroup/memory.stat | grep fault
>> pgfault 1071138
>> pgmajfault 553
>> total_pgfault 1071142
>> total_pgmajfault 553
>>
>> $ cat /dev/cgroup/A/memory.stat | grep fault
>> pgfault 199
>> pgmajfault 0
>> total_pgfault 199
>> total_pgmajfault 0
>>
>> Performance test: run page fault test(pft) wit 16 thread on faulting in 15G
>> anon pages in 16G container. There is no regression noticed on the "flt/cpu/s"
>>
>> Sample output from pft:
>> TAG pft:anon-sys-default:
>> Gb Thr CLine User System Wall flt/cpu/s fault/wsec
>> 15 16 1 0.69s 230.99s 14.62s 16972.539 268876.196
>>
>> +-------------------------------------------------------------------------+
>> N Min Max Median Avg Stddev
>> x 10 16682.962 17344.027 16913.524 16928.812 166.5362
>> + 10 16718.92 17023.453 16907.164 16902.399 88.468851
>> No difference proven at 95.0% confidence
>>
>> Signed-off-by: Ying Han <yinghan@xxxxxxxxxx>
>> ---
>> Documentation/cgroups/memory.txt | 4 +++
>> fs/ncpfs/mmap.c | 2 +
>> include/linux/memcontrol.h | 18 ++++++++++++++
>> mm/filemap.c | 1 +
>> mm/memcontrol.c | 47 ++++++++++++++++++++++++++++++++++++++
>> mm/memory.c | 2 +
>> mm/shmem.c | 2 +
>> 7 files changed, 76 insertions(+), 0 deletions(-)
>>
>> diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
>> index b6ed61c..2db6103 100644
>> --- a/Documentation/cgroups/memory.txt
>> +++ b/Documentation/cgroups/memory.txt
>> @@ -385,6 +385,8 @@ mapped_file - # of bytes of mapped file (includes tmpfs/shmem)
>> pgpgin - # of pages paged in (equivalent to # of charging events).
>> pgpgout - # of pages paged out (equivalent to # of uncharging events).
>> swap - # of bytes of swap usage
>> +pgfault - # of page faults.
>> +pgmajfault - # of major page faults.
>> inactive_anon - # of bytes of anonymous memory and swap cache memory on
>> LRU list.
>> active_anon - # of bytes of anonymous and swap cache memory on active
>> @@ -406,6 +408,8 @@ total_mapped_file - sum of all children's "cache"
>> total_pgpgin - sum of all children's "pgpgin"
>> total_pgpgout - sum of all children's "pgpgout"
>> total_swap - sum of all children's "swap"
>> +total_pgfault - sum of all children's "pgfault"
>> +total_pgmajfault - sum of all children's "pgmajfault"
>> total_inactive_anon - sum of all children's "inactive_anon"
>> total_active_anon - sum of all children's "active_anon"
>> total_inactive_file - sum of all children's "inactive_file"
>> diff --git a/fs/ncpfs/mmap.c b/fs/ncpfs/mmap.c
>> index a7c07b4..e5d71b2 100644
>> --- a/fs/ncpfs/mmap.c
>> +++ b/fs/ncpfs/mmap.c
>> @@ -16,6 +16,7 @@
>> #include <linux/mman.h>
>> #include <linux/string.h>
>> #include <linux/fcntl.h>
>> +#include <linux/memcontrol.h>
>>
>> #include <asm/uaccess.h>
>> #include <asm/system.h>
>> @@ -92,6 +93,7 @@ static int ncp_file_mmap_fault(struct vm_area_struct *area,
>> * -- wli
>> */
>> count_vm_event(PGMAJFAULT);
>> + mem_cgroup_count_vm_event(area->vm_mm, PGMAJFAULT);
>> return VM_FAULT_MAJOR;
>> }
>>
>> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
>> index 5a5ce70..45e5268 100644
>> --- a/include/linux/memcontrol.h
>> +++ b/include/linux/memcontrol.h
>> @@ -24,6 +24,7 @@ struct mem_cgroup;
>> struct page_cgroup;
>> struct page;
>> struct mm_struct;
>> +enum vm_event_item;
>>
>> /* Stats that can be updated by kernel. */
>> enum mem_cgroup_page_stat_item {
>> @@ -147,6 +148,9 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
>> gfp_t gfp_mask);
>> u64 mem_cgroup_get_limit(struct mem_cgroup *mem);
>>
>> +void mem_cgroup_pgfault(struct mem_cgroup *memcg, int val);
>> +void mem_cgroup_pgmajfault(struct mem_cgroup *memcg, int val);
>
> Do we have to expose above two functions?
> Isn't it enough to only mem_cgroup_count_vm_event?
probably not. will send another patch.
thanks
--Ying
>
>> +void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
>
>
> --
> Kind regards,
> Minchan Kim
>
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