[PATCH 6/7] mm, vmscan: enhance mm_vmscan_lru_shrink_inactive tracepoint

[Michal Hocko]

From: Michal Hocko 

mm_vmscan_lru_shrink_inactive will currently report the number of
scanned and reclaimed pages. This doesn't give us an idea how the
reclaim went except for the overall effectiveness though. Export
and show other counters which will tell us why we couldn't reclaim
some pages.
- nr_dirty, nr_writeback, nr_congested and nr_immediate tells
  us how many pages are blocked due to IO
- nr_activate tells us how many pages were moved to the active
  list
- nr_ref_keep reports how many pages are kept on the LRU due
  to references (mostly for the file pages which are about to
  go for another round through the inactive list)
- nr_unmap_fail - how many pages failed to unmap

All these are rather low level so they might change in future but the
tracepoint is already implementation specific so no tools should be
depending on its stability.

Acked-by: Hillf Danton 
Acked-by: Mel Gorman 
Signed-off-by: Michal Hocko 
---
 include/trace/events/vmscan.h | 29 ++---
 mm/vmscan.c   | 14 ++
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 7ec59e0432c4..9037c1734294 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -340,14 +340,27 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
 
TP_PROTO(int nid,
unsigned long nr_scanned, unsigned long nr_reclaimed,
+   unsigned long nr_dirty, unsigned long nr_writeback,
+   unsigned long nr_congested, unsigned long nr_immediate,
+   unsigned long nr_activate, unsigned long nr_ref_keep,
+   unsigned long nr_unmap_fail,
int priority, int file),
 
-   TP_ARGS(nid, nr_scanned, nr_reclaimed, priority, file),
+   TP_ARGS(nid, nr_scanned, nr_reclaimed, nr_dirty, nr_writeback,
+   nr_congested, nr_immediate, nr_activate, nr_ref_keep,
+   nr_unmap_fail, priority, file),
 
TP_STRUCT__entry(
__field(int, nid)
__field(unsigned long, nr_scanned)
__field(unsigned long, nr_reclaimed)
+   __field(unsigned long, nr_dirty)
+   __field(unsigned long, nr_writeback)
+   __field(unsigned long, nr_congested)
+   __field(unsigned long, nr_immediate)
+   __field(unsigned long, nr_activate)
+   __field(unsigned long, nr_ref_keep)
+   __field(unsigned long, nr_unmap_fail)
__field(int, priority)
__field(int, reclaim_flags)
),
@@ -356,14 +369,24 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
__entry->nid = nid;
__entry->nr_scanned = nr_scanned;
__entry->nr_reclaimed = nr_reclaimed;
+   __entry->nr_dirty = nr_dirty;
+   __entry->nr_writeback = nr_writeback;
+   __entry->nr_congested = nr_congested;
+   __entry->nr_immediate = nr_immediate;
+   __entry->nr_activate = nr_activate;
+   __entry->nr_ref_keep = nr_ref_keep;
+   __entry->nr_unmap_fail = nr_unmap_fail;
__entry->priority = priority;
__entry->reclaim_flags = trace_shrink_flags(file);
),
 
-   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld priority=%d flags=%s",
+   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld 
nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate=%ld 
nr_ref_keep=%ld nr_unmap_fail=%ld priority=%d flags=%s",
__entry->nid,
__entry->nr_scanned, __entry->nr_reclaimed,
-   __entry->priority,
+   __entry->nr_dirty, __entry->nr_writeback,
+   __entry->nr_congested, __entry->nr_immediate,
+   __entry->nr_activate, __entry->nr_ref_keep,
+   __entry->nr_unmap_fail, __entry->priority,
show_reclaim_flags(__entry->reclaim_flags))
 );
 
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 920e47a905c3..d05e42bee511 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -908,6 +908,9 @@ struct reclaim_stat {
unsigned nr_congested;
unsigned nr_writeback;
unsigned nr_immediate;
+   unsigned nr_activate;
+   unsigned nr_ref_keep;
+   unsigned nr_unmap_fail;
 };
 
 /*
@@ -929,6 +932,8 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
unsigned nr_reclaimed = 0;
unsigned nr_writeback = 0;
unsigned nr_immediate = 0;
+   unsigned nr_ref_keep = 0;
+   unsigned nr_unmap_fail = 0;
 
cond_resched();
 
@@ -1067,6 +1072,7 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
case PAGEREF_ACTIVATE:
goto 

[PATCH 6/7] mm, vmscan: enhance mm_vmscan_lru_shrink_inactive tracepoint

[Michal Hocko]

From: Michal Hocko 

mm_vmscan_lru_shrink_inactive will currently report the number of
scanned and reclaimed pages. This doesn't give us an idea how the
reclaim went except for the overall effectiveness though. Export
and show other counters which will tell us why we couldn't reclaim
some pages.
- nr_dirty, nr_writeback, nr_congested and nr_immediate tells
  us how many pages are blocked due to IO
- nr_activate tells us how many pages were moved to the active
  list
- nr_ref_keep reports how many pages are kept on the LRU due
  to references (mostly for the file pages which are about to
  go for another round through the inactive list)
- nr_unmap_fail - how many pages failed to unmap

All these are rather low level so they might change in future but the
tracepoint is already implementation specific so no tools should be
depending on its stability.

Acked-by: Hillf Danton 
Acked-by: Mel Gorman 
Signed-off-by: Michal Hocko 
---
 include/trace/events/vmscan.h | 29 ++---
 mm/vmscan.c   | 14 ++
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 7ec59e0432c4..9037c1734294 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -340,14 +340,27 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
 
TP_PROTO(int nid,
unsigned long nr_scanned, unsigned long nr_reclaimed,
+   unsigned long nr_dirty, unsigned long nr_writeback,
+   unsigned long nr_congested, unsigned long nr_immediate,
+   unsigned long nr_activate, unsigned long nr_ref_keep,
+   unsigned long nr_unmap_fail,
int priority, int file),
 
-   TP_ARGS(nid, nr_scanned, nr_reclaimed, priority, file),
+   TP_ARGS(nid, nr_scanned, nr_reclaimed, nr_dirty, nr_writeback,
+   nr_congested, nr_immediate, nr_activate, nr_ref_keep,
+   nr_unmap_fail, priority, file),
 
TP_STRUCT__entry(
__field(int, nid)
__field(unsigned long, nr_scanned)
__field(unsigned long, nr_reclaimed)
+   __field(unsigned long, nr_dirty)
+   __field(unsigned long, nr_writeback)
+   __field(unsigned long, nr_congested)
+   __field(unsigned long, nr_immediate)
+   __field(unsigned long, nr_activate)
+   __field(unsigned long, nr_ref_keep)
+   __field(unsigned long, nr_unmap_fail)
__field(int, priority)
__field(int, reclaim_flags)
),
@@ -356,14 +369,24 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
__entry->nid = nid;
__entry->nr_scanned = nr_scanned;
__entry->nr_reclaimed = nr_reclaimed;
+   __entry->nr_dirty = nr_dirty;
+   __entry->nr_writeback = nr_writeback;
+   __entry->nr_congested = nr_congested;
+   __entry->nr_immediate = nr_immediate;
+   __entry->nr_activate = nr_activate;
+   __entry->nr_ref_keep = nr_ref_keep;
+   __entry->nr_unmap_fail = nr_unmap_fail;
__entry->priority = priority;
__entry->reclaim_flags = trace_shrink_flags(file);
),
 
-   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld priority=%d flags=%s",
+   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld 
nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate=%ld 
nr_ref_keep=%ld nr_unmap_fail=%ld priority=%d flags=%s",
__entry->nid,
__entry->nr_scanned, __entry->nr_reclaimed,
-   __entry->priority,
+   __entry->nr_dirty, __entry->nr_writeback,
+   __entry->nr_congested, __entry->nr_immediate,
+   __entry->nr_activate, __entry->nr_ref_keep,
+   __entry->nr_unmap_fail, __entry->priority,
show_reclaim_flags(__entry->reclaim_flags))
 );
 
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 920e47a905c3..d05e42bee511 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -908,6 +908,9 @@ struct reclaim_stat {
unsigned nr_congested;
unsigned nr_writeback;
unsigned nr_immediate;
+   unsigned nr_activate;
+   unsigned nr_ref_keep;
+   unsigned nr_unmap_fail;
 };
 
 /*
@@ -929,6 +932,8 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
unsigned nr_reclaimed = 0;
unsigned nr_writeback = 0;
unsigned nr_immediate = 0;
+   unsigned nr_ref_keep = 0;
+   unsigned nr_unmap_fail = 0;
 
cond_resched();
 
@@ -1067,6 +1072,7 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
case PAGEREF_ACTIVATE:
goto activate_locked;
case PAGEREF_KEEP:
+   nr_ref_keep++;

Re: [PATCH 6/7] mm, vmscan: enhance mm_vmscan_lru_shrink_inactive tracepoint

[Hillf Danton]

On Wednesday, December 28, 2016 11:31 PM Michal Hocko wrote: 
> From: Michal Hocko 
> 
> mm_vmscan_lru_shrink_inactive will currently report the number of
> scanned and reclaimed pages. This doesn't give us an idea how the
> reclaim went except for the overall effectiveness though. Export
> and show other counters which will tell us why we couldn't reclaim
> some pages.
>   - nr_dirty, nr_writeback, nr_congested and nr_immediate tells
> us how many pages are blocked due to IO
>   - nr_activate tells us how many pages were moved to the active
> list
>   - nr_ref_keep reports how many pages are kept on the LRU due
> to references (mostly for the file pages which are about to
> go for another round through the inactive list)
>   - nr_unmap_fail - how many pages failed to unmap
> 
> All these are rather low level so they might change in future but the
> tracepoint is already implementation specific so no tools should be
> depending on its stability.
> 
> Signed-off-by: Michal Hocko 
> ---
Acked-by: Hillf Danton 

Re: [PATCH 6/7] mm, vmscan: enhance mm_vmscan_lru_shrink_inactive tracepoint

[Hillf Danton]

On Wednesday, December 28, 2016 11:31 PM Michal Hocko wrote: 
> From: Michal Hocko 
> 
> mm_vmscan_lru_shrink_inactive will currently report the number of
> scanned and reclaimed pages. This doesn't give us an idea how the
> reclaim went except for the overall effectiveness though. Export
> and show other counters which will tell us why we couldn't reclaim
> some pages.
>   - nr_dirty, nr_writeback, nr_congested and nr_immediate tells
> us how many pages are blocked due to IO
>   - nr_activate tells us how many pages were moved to the active
> list
>   - nr_ref_keep reports how many pages are kept on the LRU due
> to references (mostly for the file pages which are about to
> go for another round through the inactive list)
>   - nr_unmap_fail - how many pages failed to unmap
> 
> All these are rather low level so they might change in future but the
> tracepoint is already implementation specific so no tools should be
> depending on its stability.
> 
> Signed-off-by: Michal Hocko 
> ---
Acked-by: Hillf Danton 

[PATCH 6/7] mm, vmscan: enhance mm_vmscan_lru_shrink_inactive tracepoint

[Michal Hocko]

From: Michal Hocko 

mm_vmscan_lru_shrink_inactive will currently report the number of
scanned and reclaimed pages. This doesn't give us an idea how the
reclaim went except for the overall effectiveness though. Export
and show other counters which will tell us why we couldn't reclaim
some pages.
- nr_dirty, nr_writeback, nr_congested and nr_immediate tells
  us how many pages are blocked due to IO
- nr_activate tells us how many pages were moved to the active
  list
- nr_ref_keep reports how many pages are kept on the LRU due
  to references (mostly for the file pages which are about to
  go for another round through the inactive list)
- nr_unmap_fail - how many pages failed to unmap

All these are rather low level so they might change in future but the
tracepoint is already implementation specific so no tools should be
depending on its stability.

Signed-off-by: Michal Hocko 
---
 include/trace/events/vmscan.h | 29 ++---
 mm/vmscan.c   | 14 ++
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index cc0b4c456c78..d27606f27af7 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -348,14 +348,27 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
 
TP_PROTO(int nid,
unsigned long nr_scanned, unsigned long nr_reclaimed,
+   unsigned long nr_dirty, unsigned long nr_writeback,
+   unsigned long nr_congested, unsigned long nr_immediate,
+   unsigned long nr_activate, unsigned long nr_ref_keep,
+   unsigned long nr_unmap_fail,
int priority, int file),
 
-   TP_ARGS(nid, nr_scanned, nr_reclaimed, priority, file),
+   TP_ARGS(nid, nr_scanned, nr_reclaimed, nr_dirty, nr_writeback,
+   nr_congested, nr_immediate, nr_activate, nr_ref_keep,
+   nr_unmap_fail, priority, file),
 
TP_STRUCT__entry(
__field(int, nid)
__field(unsigned long, nr_scanned)
__field(unsigned long, nr_reclaimed)
+   __field(unsigned long, nr_dirty)
+   __field(unsigned long, nr_writeback)
+   __field(unsigned long, nr_congested)
+   __field(unsigned long, nr_immediate)
+   __field(unsigned long, nr_activate)
+   __field(unsigned long, nr_ref_keep)
+   __field(unsigned long, nr_unmap_fail)
__field(int, priority)
__field(int, reclaim_flags)
),
@@ -364,14 +377,24 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
__entry->nid = nid;
__entry->nr_scanned = nr_scanned;
__entry->nr_reclaimed = nr_reclaimed;
+   __entry->nr_dirty = nr_dirty;
+   __entry->nr_writeback = nr_writeback;
+   __entry->nr_congested = nr_congested;
+   __entry->nr_immediate = nr_immediate;
+   __entry->nr_activate = nr_activate;
+   __entry->nr_ref_keep = nr_ref_keep;
+   __entry->nr_unmap_fail = nr_unmap_fail;
__entry->priority = priority;
__entry->reclaim_flags = trace_shrink_flags(file);
),
 
-   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld priority=%d flags=%s",
+   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld 
nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate=%ld 
nr_ref_keep=%ld nr_unmap_fail=%ld priority=%d flags=%s",
__entry->nid,
__entry->nr_scanned, __entry->nr_reclaimed,
-   __entry->priority,
+   __entry->nr_dirty, __entry->nr_writeback,
+   __entry->nr_congested, __entry->nr_immediate,
+   __entry->nr_activate, __entry->nr_ref_keep,
+   __entry->nr_unmap_fail, __entry->priority,
show_reclaim_flags(__entry->reclaim_flags))
 );
 
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f6f2d828968c..a701bdd6334a 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -908,6 +908,9 @@ struct reclaim_stat {
unsigned nr_congested;
unsigned nr_writeback;
unsigned nr_immediate;
+   unsigned nr_activate;
+   unsigned nr_ref_keep;
+   unsigned nr_unmap_fail;
 };
 
 /*
@@ -929,6 +932,8 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
unsigned nr_reclaimed = 0;
unsigned nr_writeback = 0;
unsigned nr_immediate = 0;
+   unsigned nr_ref_keep = 0;
+   unsigned nr_unmap_fail = 0;
 
cond_resched();
 
@@ -1067,6 +1072,7 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
case PAGEREF_ACTIVATE:
goto activate_locked;
case PAGEREF_KEEP:
+   nr_ref_keep++;

[PATCH 6/7] mm, vmscan: enhance mm_vmscan_lru_shrink_inactive tracepoint

[Michal Hocko]

From: Michal Hocko 

mm_vmscan_lru_shrink_inactive will currently report the number of
scanned and reclaimed pages. This doesn't give us an idea how the
reclaim went except for the overall effectiveness though. Export
and show other counters which will tell us why we couldn't reclaim
some pages.
- nr_dirty, nr_writeback, nr_congested and nr_immediate tells
  us how many pages are blocked due to IO
- nr_activate tells us how many pages were moved to the active
  list
- nr_ref_keep reports how many pages are kept on the LRU due
  to references (mostly for the file pages which are about to
  go for another round through the inactive list)
- nr_unmap_fail - how many pages failed to unmap

All these are rather low level so they might change in future but the
tracepoint is already implementation specific so no tools should be
depending on its stability.

Signed-off-by: Michal Hocko 
---
 include/trace/events/vmscan.h | 29 ++---
 mm/vmscan.c   | 14 ++
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index cc0b4c456c78..d27606f27af7 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -348,14 +348,27 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
 
TP_PROTO(int nid,
unsigned long nr_scanned, unsigned long nr_reclaimed,
+   unsigned long nr_dirty, unsigned long nr_writeback,
+   unsigned long nr_congested, unsigned long nr_immediate,
+   unsigned long nr_activate, unsigned long nr_ref_keep,
+   unsigned long nr_unmap_fail,
int priority, int file),
 
-   TP_ARGS(nid, nr_scanned, nr_reclaimed, priority, file),
+   TP_ARGS(nid, nr_scanned, nr_reclaimed, nr_dirty, nr_writeback,
+   nr_congested, nr_immediate, nr_activate, nr_ref_keep,
+   nr_unmap_fail, priority, file),
 
TP_STRUCT__entry(
__field(int, nid)
__field(unsigned long, nr_scanned)
__field(unsigned long, nr_reclaimed)
+   __field(unsigned long, nr_dirty)
+   __field(unsigned long, nr_writeback)
+   __field(unsigned long, nr_congested)
+   __field(unsigned long, nr_immediate)
+   __field(unsigned long, nr_activate)
+   __field(unsigned long, nr_ref_keep)
+   __field(unsigned long, nr_unmap_fail)
__field(int, priority)
__field(int, reclaim_flags)
),
@@ -364,14 +377,24 @@ TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
__entry->nid = nid;
__entry->nr_scanned = nr_scanned;
__entry->nr_reclaimed = nr_reclaimed;
+   __entry->nr_dirty = nr_dirty;
+   __entry->nr_writeback = nr_writeback;
+   __entry->nr_congested = nr_congested;
+   __entry->nr_immediate = nr_immediate;
+   __entry->nr_activate = nr_activate;
+   __entry->nr_ref_keep = nr_ref_keep;
+   __entry->nr_unmap_fail = nr_unmap_fail;
__entry->priority = priority;
__entry->reclaim_flags = trace_shrink_flags(file);
),
 
-   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld priority=%d flags=%s",
+   TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld 
nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate=%ld 
nr_ref_keep=%ld nr_unmap_fail=%ld priority=%d flags=%s",
__entry->nid,
__entry->nr_scanned, __entry->nr_reclaimed,
-   __entry->priority,
+   __entry->nr_dirty, __entry->nr_writeback,
+   __entry->nr_congested, __entry->nr_immediate,
+   __entry->nr_activate, __entry->nr_ref_keep,
+   __entry->nr_unmap_fail, __entry->priority,
show_reclaim_flags(__entry->reclaim_flags))
 );
 
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f6f2d828968c..a701bdd6334a 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -908,6 +908,9 @@ struct reclaim_stat {
unsigned nr_congested;
unsigned nr_writeback;
unsigned nr_immediate;
+   unsigned nr_activate;
+   unsigned nr_ref_keep;
+   unsigned nr_unmap_fail;
 };
 
 /*
@@ -929,6 +932,8 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
unsigned nr_reclaimed = 0;
unsigned nr_writeback = 0;
unsigned nr_immediate = 0;
+   unsigned nr_ref_keep = 0;
+   unsigned nr_unmap_fail = 0;
 
cond_resched();
 
@@ -1067,6 +1072,7 @@ static unsigned long shrink_page_list(struct list_head 
*page_list,
case PAGEREF_ACTIVATE:
goto activate_locked;
case PAGEREF_KEEP:
+   nr_ref_keep++;
goto keep_locked;