[PATCH 1/8] tracing, vmscan: Add trace events for LRU list shrinking

From: Mel Gorman
Date: Wed Sep 15 2010 - 08:29:42 EST


This patch adds a trace event for shrink_inactive_list() and updates the
sample postprocessing script appropriately. It can be used to determine
how many pages were reclaimed and for non-lumpy reclaim where exactly the
pages were reclaimed from.

Signed-off-by: Mel Gorman <mel@xxxxxxxxx>
---
.../trace/postprocess/trace-vmscan-postprocess.pl | 39 +++++++++++++-----
include/trace/events/vmscan.h | 42 ++++++++++++++++++++
mm/vmscan.c | 6 +++
3 files changed, 77 insertions(+), 10 deletions(-)

diff --git a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
index 1b55146..b3e73dd 100644
--- a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
+++ b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
@@ -46,7 +46,7 @@ use constant HIGH_KSWAPD_LATENCY => 20;
use constant HIGH_KSWAPD_REWAKEUP => 21;
use constant HIGH_NR_SCANNED => 22;
use constant HIGH_NR_TAKEN => 23;
-use constant HIGH_NR_RECLAIM => 24;
+use constant HIGH_NR_RECLAIMED => 24;
use constant HIGH_NR_CONTIG_DIRTY => 25;

my %perprocesspid;
@@ -58,11 +58,13 @@ my $opt_read_procstat;
my $total_wakeup_kswapd;
my ($total_direct_reclaim, $total_direct_nr_scanned);
my ($total_direct_latency, $total_kswapd_latency);
+my ($total_direct_nr_reclaimed);
my ($total_direct_writepage_file_sync, $total_direct_writepage_file_async);
my ($total_direct_writepage_anon_sync, $total_direct_writepage_anon_async);
my ($total_kswapd_nr_scanned, $total_kswapd_wake);
my ($total_kswapd_writepage_file_sync, $total_kswapd_writepage_file_async);
my ($total_kswapd_writepage_anon_sync, $total_kswapd_writepage_anon_async);
+my ($total_kswapd_nr_reclaimed);

# Catch sigint and exit on request
my $sigint_report = 0;
@@ -104,7 +106,7 @@ my $regex_kswapd_wake_default = 'nid=([0-9]*) order=([0-9]*)';
my $regex_kswapd_sleep_default = 'nid=([0-9]*)';
my $regex_wakeup_kswapd_default = 'nid=([0-9]*) zid=([0-9]*) order=([0-9]*)';
my $regex_lru_isolate_default = 'isolate_mode=([0-9]*) order=([0-9]*) nr_requested=([0-9]*) nr_scanned=([0-9]*) nr_taken=([0-9]*) contig_taken=([0-9]*) contig_dirty=([0-9]*) contig_failed=([0-9]*)';
-my $regex_lru_shrink_inactive_default = 'lru=([A-Z_]*) nr_scanned=([0-9]*) nr_reclaimed=([0-9]*) priority=([0-9]*)';
+my $regex_lru_shrink_inactive_default = 'nid=([0-9]*) zid=([0-9]*) nr_scanned=([0-9]*) nr_reclaimed=([0-9]*) priority=([0-9]*) flags=([A-Z_|]*)';
my $regex_lru_shrink_active_default = 'lru=([A-Z_]*) nr_scanned=([0-9]*) nr_rotated=([0-9]*) priority=([0-9]*)';
my $regex_writepage_default = 'page=([0-9a-f]*) pfn=([0-9]*) flags=([A-Z_|]*)';

@@ -203,8 +205,8 @@ $regex_lru_shrink_inactive = generate_traceevent_regex(
"vmscan/mm_vmscan_lru_shrink_inactive",
$regex_lru_shrink_inactive_default,
"nid", "zid",
- "lru",
- "nr_scanned", "nr_reclaimed", "priority");
+ "nr_scanned", "nr_reclaimed", "priority",
+ "flags");
$regex_lru_shrink_active = generate_traceevent_regex(
"vmscan/mm_vmscan_lru_shrink_active",
$regex_lru_shrink_active_default,
@@ -375,6 +377,16 @@ EVENT_PROCESS:
my $nr_contig_dirty = $7;
$perprocesspid{$process_pid}->{HIGH_NR_SCANNED} += $nr_scanned;
$perprocesspid{$process_pid}->{HIGH_NR_CONTIG_DIRTY} += $nr_contig_dirty;
+ } elsif ($tracepoint eq "mm_vmscan_lru_shrink_inactive") {
+ $details = $5;
+ if ($details !~ /$regex_lru_shrink_inactive/o) {
+ print "WARNING: Failed to parse mm_vmscan_lru_shrink_inactive as expected\n";
+ print " $details\n";
+ print " $regex_lru_shrink_inactive/o\n";
+ next;
+ }
+ my $nr_reclaimed = $4;
+ $perprocesspid{$process_pid}->{HIGH_NR_RECLAIMED} += $nr_reclaimed;
} elsif ($tracepoint eq "mm_vmscan_writepage") {
$details = $5;
if ($details !~ /$regex_writepage/o) {
@@ -464,8 +476,8 @@ sub dump_stats {

# Print out process activity
printf("\n");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s\n", "Process", "Direct", "Wokeup", "Pages", "Pages", "Pages", "Time");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s\n", "details", "Rclms", "Kswapd", "Scanned", "Sync-IO", "ASync-IO", "Stalled");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s\n", "Process", "Direct", "Wokeup", "Pages", "Pages", "Pages", "Pages", "Time");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s\n", "details", "Rclms", "Kswapd", "Scanned", "Rclmed", "Sync-IO", "ASync-IO", "Stalled");
foreach $process_pid (keys %stats) {

if (!$stats{$process_pid}->{MM_VMSCAN_DIRECT_RECLAIM_BEGIN}) {
@@ -475,6 +487,7 @@ sub dump_stats {
$total_direct_reclaim += $stats{$process_pid}->{MM_VMSCAN_DIRECT_RECLAIM_BEGIN};
$total_wakeup_kswapd += $stats{$process_pid}->{MM_VMSCAN_WAKEUP_KSWAPD};
$total_direct_nr_scanned += $stats{$process_pid}->{HIGH_NR_SCANNED};
+ $total_direct_nr_reclaimed += $stats{$process_pid}->{HIGH_NR_RECLAIMED};
$total_direct_writepage_file_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC};
$total_direct_writepage_anon_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC};
$total_direct_writepage_file_async += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC};
@@ -489,11 +502,12 @@ sub dump_stats {
$index++;
}

- printf("%-" . $max_strlen . "s %8d %10d %8u %8u %8u %8.3f",
+ printf("%-" . $max_strlen . "s %8d %10d %8u %8u %8u %8u %8.3f",
$process_pid,
$stats{$process_pid}->{MM_VMSCAN_DIRECT_RECLAIM_BEGIN},
$stats{$process_pid}->{MM_VMSCAN_WAKEUP_KSWAPD},
$stats{$process_pid}->{HIGH_NR_SCANNED},
+ $stats{$process_pid}->{HIGH_NR_RECLAIMED},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_ASYNC},
$this_reclaim_delay / 1000);
@@ -529,8 +543,8 @@ sub dump_stats {

# Print out kswapd activity
printf("\n");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Kswapd", "Kswapd", "Order", "Pages", "Pages", "Pages");
- printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Instance", "Wakeups", "Re-wakeup", "Scanned", "Sync-IO", "ASync-IO");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Kswapd", "Kswapd", "Order", "Pages", "Pages", "Pages", "Pages");
+ printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s\n", "Instance", "Wakeups", "Re-wakeup", "Scanned", "Rclmed", "Sync-IO", "ASync-IO");
foreach $process_pid (keys %stats) {

if (!$stats{$process_pid}->{MM_VMSCAN_KSWAPD_WAKE}) {
@@ -539,16 +553,18 @@ sub dump_stats {

$total_kswapd_wake += $stats{$process_pid}->{MM_VMSCAN_KSWAPD_WAKE};
$total_kswapd_nr_scanned += $stats{$process_pid}->{HIGH_NR_SCANNED};
+ $total_kswapd_nr_reclaimed += $stats{$process_pid}->{HIGH_NR_RECLAIMED};
$total_kswapd_writepage_file_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC};
$total_kswapd_writepage_anon_sync += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC};
$total_kswapd_writepage_file_async += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC};
$total_kswapd_writepage_anon_async += $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_ASYNC};

- printf("%-" . $max_strlen . "s %8d %10d %8u %8i %8u",
+ printf("%-" . $max_strlen . "s %8d %10d %8u %8u %8i %8u",
$process_pid,
$stats{$process_pid}->{MM_VMSCAN_KSWAPD_WAKE},
$stats{$process_pid}->{HIGH_KSWAPD_REWAKEUP},
$stats{$process_pid}->{HIGH_NR_SCANNED},
+ $stats{$process_pid}->{HIGH_NR_RECLAIMED},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC},
$stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC} + $stats{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_ASYNC});

@@ -579,6 +595,7 @@ sub dump_stats {
print "\nSummary\n";
print "Direct reclaims: $total_direct_reclaim\n";
print "Direct reclaim pages scanned: $total_direct_nr_scanned\n";
+ print "Direct reclaim pages reclaimed: $total_direct_nr_reclaimed\n";
print "Direct reclaim write file sync I/O: $total_direct_writepage_file_sync\n";
print "Direct reclaim write anon sync I/O: $total_direct_writepage_anon_sync\n";
print "Direct reclaim write file async I/O: $total_direct_writepage_file_async\n";
@@ -588,6 +605,7 @@ sub dump_stats {
print "\n";
print "Kswapd wakeups: $total_kswapd_wake\n";
print "Kswapd pages scanned: $total_kswapd_nr_scanned\n";
+ print "Kswapd pages reclaimed: $total_kswapd_nr_reclaimed\n";
print "Kswapd reclaim write file sync I/O: $total_kswapd_writepage_file_sync\n";
print "Kswapd reclaim write anon sync I/O: $total_kswapd_writepage_anon_sync\n";
print "Kswapd reclaim write file async I/O: $total_kswapd_writepage_file_async\n";
@@ -612,6 +630,7 @@ sub aggregate_perprocesspid() {
$perprocess{$process}->{MM_VMSCAN_WAKEUP_KSWAPD} += $perprocesspid{$process_pid}->{MM_VMSCAN_WAKEUP_KSWAPD};
$perprocess{$process}->{HIGH_KSWAPD_REWAKEUP} += $perprocesspid{$process_pid}->{HIGH_KSWAPD_REWAKEUP};
$perprocess{$process}->{HIGH_NR_SCANNED} += $perprocesspid{$process_pid}->{HIGH_NR_SCANNED};
+ $perprocess{$process}->{HIGH_NR_RECLAIMED} += $perprocesspid{$process_pid}->{HIGH_NR_RECLAIMED};
$perprocess{$process}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC} += $perprocesspid{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_SYNC};
$perprocess{$process}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC} += $perprocesspid{$process_pid}->{MM_VMSCAN_WRITEPAGE_ANON_SYNC};
$perprocess{$process}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC} += $perprocesspid{$process_pid}->{MM_VMSCAN_WRITEPAGE_FILE_ASYNC};
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 370aa5a..ecf9521 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -10,6 +10,7 @@

#define RECLAIM_WB_ANON 0x0001u
#define RECLAIM_WB_FILE 0x0002u
+#define RECLAIM_WB_MIXED 0x0010u
#define RECLAIM_WB_SYNC 0x0004u
#define RECLAIM_WB_ASYNC 0x0008u

@@ -17,6 +18,7 @@
(flags) ? __print_flags(flags, "|", \
{RECLAIM_WB_ANON, "RECLAIM_WB_ANON"}, \
{RECLAIM_WB_FILE, "RECLAIM_WB_FILE"}, \
+ {RECLAIM_WB_MIXED, "RECLAIM_WB_MIXED"}, \
{RECLAIM_WB_SYNC, "RECLAIM_WB_SYNC"}, \
{RECLAIM_WB_ASYNC, "RECLAIM_WB_ASYNC"} \
) : "RECLAIM_WB_NONE"
@@ -26,6 +28,12 @@
(sync == PAGEOUT_IO_SYNC ? RECLAIM_WB_SYNC : RECLAIM_WB_ASYNC) \
)

+#define trace_shrink_flags(file, sync) ( \
+ (sync == PAGEOUT_IO_SYNC ? RECLAIM_WB_MIXED : \
+ (file ? RECLAIM_WB_FILE : RECLAIM_WB_ANON)) | \
+ (sync == PAGEOUT_IO_SYNC ? RECLAIM_WB_SYNC : RECLAIM_WB_ASYNC) \
+ )
+
TRACE_EVENT(mm_vmscan_kswapd_sleep,

TP_PROTO(int nid),
@@ -269,6 +277,40 @@ TRACE_EVENT(mm_vmscan_writepage,
show_reclaim_flags(__entry->reclaim_flags))
);

+TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
+
+ TP_PROTO(int nid, int zid,
+ unsigned long nr_scanned, unsigned long nr_reclaimed,
+ int priority, int reclaim_flags),
+
+ TP_ARGS(nid, zid, nr_scanned, nr_reclaimed, priority, reclaim_flags),
+
+ TP_STRUCT__entry(
+ __field(int, nid)
+ __field(int, zid)
+ __field(unsigned long, nr_scanned)
+ __field(unsigned long, nr_reclaimed)
+ __field(int, priority)
+ __field(int, reclaim_flags)
+ ),
+
+ TP_fast_assign(
+ __entry->nid = nid;
+ __entry->zid = zid;
+ __entry->nr_scanned = nr_scanned;
+ __entry->nr_reclaimed = nr_reclaimed;
+ __entry->priority = priority;
+ __entry->reclaim_flags = reclaim_flags;
+ ),
+
+ TP_printk("nid=%d zid=%d nr_scanned=%ld nr_reclaimed=%ld priority=%d flags=%s",
+ __entry->nid, __entry->zid,
+ __entry->nr_scanned, __entry->nr_reclaimed,
+ __entry->priority,
+ show_reclaim_flags(__entry->reclaim_flags))
+);
+
+
#endif /* _TRACE_VMSCAN_H */

/* This part must be outside protection */
diff --git a/mm/vmscan.c b/mm/vmscan.c
index c391c32..652650f 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1359,6 +1359,12 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
__count_zone_vm_events(PGSTEAL, zone, nr_reclaimed);

putback_lru_pages(zone, sc, nr_anon, nr_file, &page_list);
+
+ trace_mm_vmscan_lru_shrink_inactive(zone->zone_pgdat->node_id,
+ zone_idx(zone),
+ nr_scanned, nr_reclaimed,
+ priority,
+ trace_shrink_flags(file, sc->lumpy_reclaim_mode));
return nr_reclaimed;
}

--
1.7.1

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