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authorMel Gorman <mel@csn.ul.ie>2009-09-21 20:02:47 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-22 10:17:34 -0400
commitc9d05cfc001fef3d6d37651e19ab9227a32b71f5 (patch)
treeac5f54c9fcf8336c7787fca63875b18621ee3fd1 /Documentation
parent0d3d062a6e289e065bd0aa537a6806a1806bf8aa (diff)
tracing, page-allocator: add a postprocessing script for page-allocator-related ftrace events
This patch adds a simple post-processing script for the page-allocator-related trace events. It can be used to give an indication of who the most allocator-intensive processes are and how often the zone lock was taken during the tracing period. Example output looks like Process Pages Pages Pages Pages PCPU PCPU PCPU Fragment Fragment MigType Fragment Fragment Unknown details allocd allocd freed freed pages drains refills Fallback Causing Changed Severe Moderate under lock direct pagevec drain swapper-0 0 0 2 0 0 0 0 0 0 0 0 0 0 Xorg-3770 10603 5952 3685 6978 5996 194 192 0 0 0 0 0 0 modprobe-21397 51 0 0 86 31 1 0 0 0 0 0 0 0 xchat-5370 228 93 0 0 0 0 3 0 0 0 0 0 0 awesome-4317 32 32 0 0 0 0 32 0 0 0 0 0 0 thinkfan-3863 2 0 1 1 0 0 0 0 0 0 0 0 0 hald-addon-stor-3935 2 0 0 0 0 0 0 0 0 0 0 0 0 akregator-4506 1 1 0 0 0 0 1 0 0 0 0 0 0 xmms-14888 0 0 1 0 0 0 0 0 0 0 0 0 0 khelper-12 1 0 0 0 0 0 0 0 0 0 0 0 0 Optionally, the output can include information on the parent or aggregate based on process name instead of aggregating based on each pid. Example output including parent information and stripped out the PID looks something like; Process Pages Pages Pages Pages PCPU PCPU PCPU Fragment Fragment MigType Fragment Fragment Unknown details allocd allocd freed freed pages drains refills Fallback Causing Changed Severe Moderate under lock direct pagevec drain gdm-3756 :: Xorg-3770 3796 2976 99 3813 3224 104 98 0 0 0 0 0 0 init-1 :: hald-3892 1 0 0 0 0 0 0 0 0 0 0 0 0 git-21447 :: editor-21448 4 0 4 0 0 0 0 0 0 0 0 0 0 This says that Xorg allocated 3796 pages and it's parent process is gdm with a PID of 3756; The postprocessor parses the text output of tracing. While there is a binary format, the expectation is that the binary output can be readily translated into text and post-processed offline. Obviously if the text format changes, the parser will break but the regular expression parser is fairly rudimentary so should be readily adjustable. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Reviewed-by: Ingo Molnar <mingo@elte.hu> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Ming Chun <macli@brc.ubc.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/trace/postprocess/trace-pagealloc-postprocess.pl418
1 files changed, 418 insertions, 0 deletions
diff --git a/Documentation/trace/postprocess/trace-pagealloc-postprocess.pl b/Documentation/trace/postprocess/trace-pagealloc-postprocess.pl
new file mode 100644
index 000000000000..7df50e8cf4d9
--- /dev/null
+++ b/Documentation/trace/postprocess/trace-pagealloc-postprocess.pl
@@ -0,0 +1,418 @@
1#!/usr/bin/perl
2# This is a POC (proof of concept or piece of crap, take your pick) for reading the
3# text representation of trace output related to page allocation. It makes an attempt
4# to extract some high-level information on what is going on. The accuracy of the parser
5# may vary considerably
6#
7# Example usage: trace-pagealloc-postprocess.pl < /sys/kernel/debug/tracing/trace_pipe
8# other options
9# --prepend-parent Report on the parent proc and PID
10# --read-procstat If the trace lacks process info, get it from /proc
11# --ignore-pid Aggregate processes of the same name together
12#
13# Copyright (c) IBM Corporation 2009
14# Author: Mel Gorman <mel@csn.ul.ie>
15use strict;
16use Getopt::Long;
17
18# Tracepoint events
19use constant MM_PAGE_ALLOC => 1;
20use constant MM_PAGE_FREE_DIRECT => 2;
21use constant MM_PAGEVEC_FREE => 3;
22use constant MM_PAGE_PCPU_DRAIN => 4;
23use constant MM_PAGE_ALLOC_ZONE_LOCKED => 5;
24use constant MM_PAGE_ALLOC_EXTFRAG => 6;
25use constant EVENT_UNKNOWN => 7;
26
27# Constants used to track state
28use constant STATE_PCPU_PAGES_DRAINED => 8;
29use constant STATE_PCPU_PAGES_REFILLED => 9;
30
31# High-level events extrapolated from tracepoints
32use constant HIGH_PCPU_DRAINS => 10;
33use constant HIGH_PCPU_REFILLS => 11;
34use constant HIGH_EXT_FRAGMENT => 12;
35use constant HIGH_EXT_FRAGMENT_SEVERE => 13;
36use constant HIGH_EXT_FRAGMENT_MODERATE => 14;
37use constant HIGH_EXT_FRAGMENT_CHANGED => 15;
38
39my %perprocesspid;
40my %perprocess;
41my $opt_ignorepid;
42my $opt_read_procstat;
43my $opt_prepend_parent;
44
45# Catch sigint and exit on request
46my $sigint_report = 0;
47my $sigint_exit = 0;
48my $sigint_pending = 0;
49my $sigint_received = 0;
50sub sigint_handler {
51 my $current_time = time;
52 if ($current_time - 2 > $sigint_received) {
53 print "SIGINT received, report pending. Hit ctrl-c again to exit\n";
54 $sigint_report = 1;
55 } else {
56 if (!$sigint_exit) {
57 print "Second SIGINT received quickly, exiting\n";
58 }
59 $sigint_exit++;
60 }
61
62 if ($sigint_exit > 3) {
63 print "Many SIGINTs received, exiting now without report\n";
64 exit;
65 }
66
67 $sigint_received = $current_time;
68 $sigint_pending = 1;
69}
70$SIG{INT} = "sigint_handler";
71
72# Parse command line options
73GetOptions(
74 'ignore-pid' => \$opt_ignorepid,
75 'read-procstat' => \$opt_read_procstat,
76 'prepend-parent' => \$opt_prepend_parent,
77);
78
79# Defaults for dynamically discovered regex's
80my $regex_fragdetails_default = 'page=([0-9a-f]*) pfn=([0-9]*) alloc_order=([-0-9]*) fallback_order=([-0-9]*) pageblock_order=([-0-9]*) alloc_migratetype=([-0-9]*) fallback_migratetype=([-0-9]*) fragmenting=([-0-9]) change_ownership=([-0-9])';
81
82# Dyanically discovered regex
83my $regex_fragdetails;
84
85# Static regex used. Specified like this for readability and for use with /o
86# (process_pid) (cpus ) ( time ) (tpoint ) (details)
87my $regex_traceevent = '\s*([a-zA-Z0-9-]*)\s*(\[[0-9]*\])\s*([0-9.]*):\s*([a-zA-Z_]*):\s*(.*)';
88my $regex_statname = '[-0-9]*\s\((.*)\).*';
89my $regex_statppid = '[-0-9]*\s\(.*\)\s[A-Za-z]\s([0-9]*).*';
90
91sub generate_traceevent_regex {
92 my $event = shift;
93 my $default = shift;
94 my $regex;
95
96 # Read the event format or use the default
97 if (!open (FORMAT, "/sys/kernel/debug/tracing/events/$event/format")) {
98 $regex = $default;
99 } else {
100 my $line;
101 while (!eof(FORMAT)) {
102 $line = <FORMAT>;
103 if ($line =~ /^print fmt:\s"(.*)",.*/) {
104 $regex = $1;
105 $regex =~ s/%p/\([0-9a-f]*\)/g;
106 $regex =~ s/%d/\([-0-9]*\)/g;
107 $regex =~ s/%lu/\([0-9]*\)/g;
108 }
109 }
110 }
111
112 # Verify fields are in the right order
113 my $tuple;
114 foreach $tuple (split /\s/, $regex) {
115 my ($key, $value) = split(/=/, $tuple);
116 my $expected = shift;
117 if ($key ne $expected) {
118 print("WARNING: Format not as expected '$key' != '$expected'");
119 $regex =~ s/$key=\((.*)\)/$key=$1/;
120 }
121 }
122
123 if (defined shift) {
124 die("Fewer fields than expected in format");
125 }
126
127 return $regex;
128}
129$regex_fragdetails = generate_traceevent_regex("kmem/mm_page_alloc_extfrag",
130 $regex_fragdetails_default,
131 "page", "pfn",
132 "alloc_order", "fallback_order", "pageblock_order",
133 "alloc_migratetype", "fallback_migratetype",
134 "fragmenting", "change_ownership");
135
136sub read_statline($) {
137 my $pid = $_[0];
138 my $statline;
139
140 if (open(STAT, "/proc/$pid/stat")) {
141 $statline = <STAT>;
142 close(STAT);
143 }
144
145 if ($statline eq '') {
146 $statline = "-1 (UNKNOWN_PROCESS_NAME) R 0";
147 }
148
149 return $statline;
150}
151
152sub guess_process_pid($$) {
153 my $pid = $_[0];
154 my $statline = $_[1];
155
156 if ($pid == 0) {
157 return "swapper-0";
158 }
159
160 if ($statline !~ /$regex_statname/o) {
161 die("Failed to math stat line for process name :: $statline");
162 }
163 return "$1-$pid";
164}
165
166sub parent_info($$) {
167 my $pid = $_[0];
168 my $statline = $_[1];
169 my $ppid;
170
171 if ($pid == 0) {
172 return "NOPARENT-0";
173 }
174
175 if ($statline !~ /$regex_statppid/o) {
176 die("Failed to match stat line process ppid:: $statline");
177 }
178
179 # Read the ppid stat line
180 $ppid = $1;
181 return guess_process_pid($ppid, read_statline($ppid));
182}
183
184sub process_events {
185 my $traceevent;
186 my $process_pid;
187 my $cpus;
188 my $timestamp;
189 my $tracepoint;
190 my $details;
191 my $statline;
192
193 # Read each line of the event log
194EVENT_PROCESS:
195 while ($traceevent = <STDIN>) {
196 if ($traceevent =~ /$regex_traceevent/o) {
197 $process_pid = $1;
198 $tracepoint = $4;
199
200 if ($opt_read_procstat || $opt_prepend_parent) {
201 $process_pid =~ /(.*)-([0-9]*)$/;
202 my $process = $1;
203 my $pid = $2;
204
205 $statline = read_statline($pid);
206
207 if ($opt_read_procstat && $process eq '') {
208 $process_pid = guess_process_pid($pid, $statline);
209 }
210
211 if ($opt_prepend_parent) {
212 $process_pid = parent_info($pid, $statline) . " :: $process_pid";
213 }
214 }
215
216 # Unnecessary in this script. Uncomment if required
217 # $cpus = $2;
218 # $timestamp = $3;
219 } else {
220 next;
221 }
222
223 # Perl Switch() sucks majorly
224 if ($tracepoint eq "mm_page_alloc") {
225 $perprocesspid{$process_pid}->{MM_PAGE_ALLOC}++;
226 } elsif ($tracepoint eq "mm_page_free_direct") {
227 $perprocesspid{$process_pid}->{MM_PAGE_FREE_DIRECT}++;
228 } elsif ($tracepoint eq "mm_pagevec_free") {
229 $perprocesspid{$process_pid}->{MM_PAGEVEC_FREE}++;
230 } elsif ($tracepoint eq "mm_page_pcpu_drain") {
231 $perprocesspid{$process_pid}->{MM_PAGE_PCPU_DRAIN}++;
232 $perprocesspid{$process_pid}->{STATE_PCPU_PAGES_DRAINED}++;
233 } elsif ($tracepoint eq "mm_page_alloc_zone_locked") {
234 $perprocesspid{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED}++;
235 $perprocesspid{$process_pid}->{STATE_PCPU_PAGES_REFILLED}++;
236 } elsif ($tracepoint eq "mm_page_alloc_extfrag") {
237
238 # Extract the details of the event now
239 $details = $5;
240
241 my ($page, $pfn);
242 my ($alloc_order, $fallback_order, $pageblock_order);
243 my ($alloc_migratetype, $fallback_migratetype);
244 my ($fragmenting, $change_ownership);
245
246 if ($details !~ /$regex_fragdetails/o) {
247 print "WARNING: Failed to parse mm_page_alloc_extfrag as expected\n";
248 next;
249 }
250
251 $perprocesspid{$process_pid}->{MM_PAGE_ALLOC_EXTFRAG}++;
252 $page = $1;
253 $pfn = $2;
254 $alloc_order = $3;
255 $fallback_order = $4;
256 $pageblock_order = $5;
257 $alloc_migratetype = $6;
258 $fallback_migratetype = $7;
259 $fragmenting = $8;
260 $change_ownership = $9;
261
262 if ($fragmenting) {
263 $perprocesspid{$process_pid}->{HIGH_EXT_FRAG}++;
264 if ($fallback_order <= 3) {
265 $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_SEVERE}++;
266 } else {
267 $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_MODERATE}++;
268 }
269 }
270 if ($change_ownership) {
271 $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_CHANGED}++;
272 }
273 } else {
274 $perprocesspid{$process_pid}->{EVENT_UNKNOWN}++;
275 }
276
277 # Catch a full pcpu drain event
278 if ($perprocesspid{$process_pid}->{STATE_PCPU_PAGES_DRAINED} &&
279 $tracepoint ne "mm_page_pcpu_drain") {
280
281 $perprocesspid{$process_pid}->{HIGH_PCPU_DRAINS}++;
282 $perprocesspid{$process_pid}->{STATE_PCPU_PAGES_DRAINED} = 0;
283 }
284
285 # Catch a full pcpu refill event
286 if ($perprocesspid{$process_pid}->{STATE_PCPU_PAGES_REFILLED} &&
287 $tracepoint ne "mm_page_alloc_zone_locked") {
288 $perprocesspid{$process_pid}->{HIGH_PCPU_REFILLS}++;
289 $perprocesspid{$process_pid}->{STATE_PCPU_PAGES_REFILLED} = 0;
290 }
291
292 if ($sigint_pending) {
293 last EVENT_PROCESS;
294 }
295 }
296}
297
298sub dump_stats {
299 my $hashref = shift;
300 my %stats = %$hashref;
301
302 # Dump per-process stats
303 my $process_pid;
304 my $max_strlen = 0;
305
306 # Get the maximum process name
307 foreach $process_pid (keys %perprocesspid) {
308 my $len = length($process_pid);
309 if ($len > $max_strlen) {
310 $max_strlen = $len;
311 }
312 }
313 $max_strlen += 2;
314
315 printf("\n");
316 printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s\n",
317 "Process", "Pages", "Pages", "Pages", "Pages", "PCPU", "PCPU", "PCPU", "Fragment", "Fragment", "MigType", "Fragment", "Fragment", "Unknown");
318 printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s\n",
319 "details", "allocd", "allocd", "freed", "freed", "pages", "drains", "refills", "Fallback", "Causing", "Changed", "Severe", "Moderate", "");
320
321 printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s\n",
322 "", "", "under lock", "direct", "pagevec", "drain", "", "", "", "", "", "", "", "");
323
324 foreach $process_pid (keys %stats) {
325 # Dump final aggregates
326 if ($stats{$process_pid}->{STATE_PCPU_PAGES_DRAINED}) {
327 $stats{$process_pid}->{HIGH_PCPU_DRAINS}++;
328 $stats{$process_pid}->{STATE_PCPU_PAGES_DRAINED} = 0;
329 }
330 if ($stats{$process_pid}->{STATE_PCPU_PAGES_REFILLED}) {
331 $stats{$process_pid}->{HIGH_PCPU_REFILLS}++;
332 $stats{$process_pid}->{STATE_PCPU_PAGES_REFILLED} = 0;
333 }
334
335 printf("%-" . $max_strlen . "s %8d %10d %8d %8d %8d %8d %8d %8d %8d %8d %8d %8d %8d\n",
336 $process_pid,
337 $stats{$process_pid}->{MM_PAGE_ALLOC},
338 $stats{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED},
339 $stats{$process_pid}->{MM_PAGE_FREE_DIRECT},
340 $stats{$process_pid}->{MM_PAGEVEC_FREE},
341 $stats{$process_pid}->{MM_PAGE_PCPU_DRAIN},
342 $stats{$process_pid}->{HIGH_PCPU_DRAINS},
343 $stats{$process_pid}->{HIGH_PCPU_REFILLS},
344 $stats{$process_pid}->{MM_PAGE_ALLOC_EXTFRAG},
345 $stats{$process_pid}->{HIGH_EXT_FRAG},
346 $stats{$process_pid}->{HIGH_EXT_FRAGMENT_CHANGED},
347 $stats{$process_pid}->{HIGH_EXT_FRAGMENT_SEVERE},
348 $stats{$process_pid}->{HIGH_EXT_FRAGMENT_MODERATE},
349 $stats{$process_pid}->{EVENT_UNKNOWN});
350 }
351}
352
353sub aggregate_perprocesspid() {
354 my $process_pid;
355 my $process;
356 undef %perprocess;
357
358 foreach $process_pid (keys %perprocesspid) {
359 $process = $process_pid;
360 $process =~ s/-([0-9])*$//;
361 if ($process eq '') {
362 $process = "NO_PROCESS_NAME";
363 }
364
365 $perprocess{$process}->{MM_PAGE_ALLOC} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC};
366 $perprocess{$process}->{MM_PAGE_ALLOC_ZONE_LOCKED} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED};
367 $perprocess{$process}->{MM_PAGE_FREE_DIRECT} += $perprocesspid{$process_pid}->{MM_PAGE_FREE_DIRECT};
368 $perprocess{$process}->{MM_PAGEVEC_FREE} += $perprocesspid{$process_pid}->{MM_PAGEVEC_FREE};
369 $perprocess{$process}->{MM_PAGE_PCPU_DRAIN} += $perprocesspid{$process_pid}->{MM_PAGE_PCPU_DRAIN};
370 $perprocess{$process}->{HIGH_PCPU_DRAINS} += $perprocesspid{$process_pid}->{HIGH_PCPU_DRAINS};
371 $perprocess{$process}->{HIGH_PCPU_REFILLS} += $perprocesspid{$process_pid}->{HIGH_PCPU_REFILLS};
372 $perprocess{$process}->{MM_PAGE_ALLOC_EXTFRAG} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC_EXTFRAG};
373 $perprocess{$process}->{HIGH_EXT_FRAG} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAG};
374 $perprocess{$process}->{HIGH_EXT_FRAGMENT_CHANGED} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_CHANGED};
375 $perprocess{$process}->{HIGH_EXT_FRAGMENT_SEVERE} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_SEVERE};
376 $perprocess{$process}->{HIGH_EXT_FRAGMENT_MODERATE} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_MODERATE};
377 $perprocess{$process}->{EVENT_UNKNOWN} += $perprocesspid{$process_pid}->{EVENT_UNKNOWN};
378 }
379}
380
381sub report() {
382 if (!$opt_ignorepid) {
383 dump_stats(\%perprocesspid);
384 } else {
385 aggregate_perprocesspid();
386 dump_stats(\%perprocess);
387 }
388}
389
390# Process events or signals until neither is available
391sub signal_loop() {
392 my $sigint_processed;
393 do {
394 $sigint_processed = 0;
395 process_events();
396
397 # Handle pending signals if any
398 if ($sigint_pending) {
399 my $current_time = time;
400
401 if ($sigint_exit) {
402 print "Received exit signal\n";
403 $sigint_pending = 0;
404 }
405 if ($sigint_report) {
406 if ($current_time >= $sigint_received + 2) {
407 report();
408 $sigint_report = 0;
409 $sigint_pending = 0;
410 $sigint_processed = 1;
411 }
412 }
413 }
414 } while ($sigint_pending || $sigint_processed);
415}
416
417signal_loop();
418report();
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