perf: memory leak in perf top

, al=<optimized out>, hists=<optimized out>) at util/hist.c:611

, al=<optimized out>, hists=<optimized out>) at util/hist.c:611

perf top comsumes too much memory than it need.

Using following commands:

 # yes '' > /dev/null
 # perf top -e raw_syscalls:sys_enter

System will quickly become unresponsive because of out of memory.

Using GDB I find two call stacks of malloc. See below.

[call stack 1]

#0 __GI___libc_malloc (bytes=140723951319552) at malloc.c:2841 #1 0x00000000004b7246 in memdup (src=0x7f515e04b054, len=68) at ../lib/string.c:29
#2 0x00000000004f9299 in hist_entry__init (sample_self=true, template=0x7ffcd9213a80, he=0xa37da50) at util/hist.c:401 #3 hist_entry__new (template=template@entry=0x7ffcd9213a80 <mailto:%28template=template@entry=0x7ffcd9213a80>, sample_self=sample_self@entry=true) <mailto:sample_self=sample_self@entry=true%29> at util/hist.c:458 #4 0x00000000004fa13f in hists__findnew_entry (hists=0x3549d30, hists=0x3549d30, al=0x7ffcd9213ca0, sample_self=true, entry=0x 7ffcd9213a80) at util/hist.c:544
#5 __hists__add_entry (hists=0x3549d30, al=0x7ffcd9213ca0, sym_parent=<optimized out>, bi=bi@entry=0x0 <mailto:bi=bi@entry=0x0>, mi=mi@entry=0x0 <mailto:mi=mi@entry=0x0>, sampl e=<optimized out>, sample_self=sample_self@entry=true <mailto:sample_self=sample_self@entry=true>, ops=ops@entry=0x0) <mailto:ops=ops@entry=0x0%29> at util/hist.c:600
#6 0x00000000004fa3d6 in hists__add_entry (sample_self=true, sample=<optimized out>, mi=0x0, bi=0x0, sym_parent=<optimized out

Quoted 1 line

, al=<optimized out>, hists=<optimized out>) at util/hist.c:611

#7 iter_add_single_normal_entry (iter=0x7ffcd9213ce0, al=<optimized out>) at util/hist.c:823
#8 0x00000000004fc3c5 in hist_entry_iter__add (iter=0x7ffcd9213ce0, al=0x7ffcd9213ca0, max_stack_depth=<optimized out>, arg=0x 7ffcd9214120) at util/hist.c:1030
#9 0x00000000004536d7 in perf_event__process_sample (machine=<optimized out>, sample=0x7ffcd9213d30, evsel=0x3549bb0, event=<o
ptimized out>, tool=0x7ffcd9214120) at builtin-top.c:800
#10 perf_top__mmap_read_idx (top=top@entry=0x7ffcd9214120 <mailto:%28top=top@entry=0x7ffcd9214120>, idx=idx@entry=0) <mailto:idx=idx@entry=0%29> at builtin-top.c:866
#11 0x00000000004559fd in perf_top__mmap_read (top=0x7ffcd9214120) at builtin-top.c:883
#12 __cmd_top (top=0x7ffcd9214120) at builtin-top.c:1018
#13 cmd_top (argc=<optimized out>, argv=<optimized out>, prefix=<optimized out>) at builtin-top.c:1344
#14 0x0000000000493561 in run_builtin (p=p@entry=0x948000 <mailto:%28p=p@entry=0x948000> <commands+288>, argc=argc@entry=4 <mailto:argc=argc@entry=4>, argv=argv@entry=0x7ffcd92199b0) <mailto:argv=argv@entry=0x7ffcd92199b0%29> at
perf.c:357
#15 0x0000000000437157 in handle_internal_command (argv=0x7ffcd92199b0, argc=4) at perf.c:419
#16 run_argv (argv=0x7ffcd9219720, argcp=0x7ffcd921972c) at perf.c:465 #17 main (argc=4, argv=0x7ffcd92199b0) at perf.c:609

[call stack 2]

#0 __GI___libc_malloc (bytes=140723951319456) at malloc.c:2841 #1 0x00000000005766de in trace_seq_init (s=0x7ffcd92139b0) at trace-seq.c:60 #2 0x00000000004f7047 in get_trace_output (he=0x7ffcd9213a80) at util/sort.c:584

#3 sort__trace_cmp (left=0x40e6d30, right=0x7ffcd9213a80) at util/sort.c:606 #4 0x00000000004fa007 in hist_entry__cmp (right=0x7ffcd9213a80, left=0x40e6d30) at util/hist.c:1072
#5 hists__findnew_entry (hists=0x3549d30, hists=0x3549d30, al=0x7ffcd9213ca0, sample_self=true, entry=0x7ffcd9213a80) at util/ hist.c:509
#6 __hists__add_entry (hists=0x3549d30, al=0x7ffcd9213ca0, sym_parent=<optimized out>, bi=bi@entry=0x0 <mailto:bi=bi@entry=0x0>, mi=mi@entry=0x0 <mailto:mi=mi@entry=0x0>, sampl
e=<optimized out>, sample_self=sample_self@entry=true <mailto:sample_self=sample_self@entry=true>, ops=ops@entry=0x0) <mailto:ops=ops@entry=0x0%29> at util/hist.c:600
#7 0x00000000004fa3d6 in hists__add_entry (sample_self=true, sample=<optimized out>, mi=0x0, bi=0x0, sym_parent=<optimized out

Quoted 1 line

, al=<optimized out>, hists=<optimized out>) at util/hist.c:611

#8 iter_add_single_normal_entry (iter=0x7ffcd9213ce0, al=<optimized out>) at util/hist.c:823
#9 0x00000000004fc3c5 in hist_entry_iter__add (iter=0x7ffcd9213ce0, al=0x7ffcd9213ca0, max_stack_depth=<optimized out>, arg=0x 7ffcd9214120) at util/hist.c:1030
#10 0x00000000004536d7 in perf_event__process_sample (machine=<optimized out>, sample=0x7ffcd9213d30, evsel=0x3549bb0, event=<o
ptimized out>, tool=0x7ffcd9214120) at builtin-top.c:800
#11 perf_top__mmap_read_idx (top=top@entry=0x7ffcd9214120 <mailto:%28top=top@entry=0x7ffcd9214120>, idx=idx@entry=0) <mailto:idx=idx@entry=0%29> at builtin-top.c:866
#12 0x00000000004559fd in perf_top__mmap_read (top=0x7ffcd9214120) at builtin-top.c:883
#13 __cmd_top (top=0x7ffcd9214120) at builtin-top.c:1018
#14 cmd_top (argc=<optimized out>, argv=<optimized out>, prefix=<optimized out>) at builtin-top.c:1344
#15 0x0000000000493561 in run_builtin (p=p@entry=0x948000 <mailto:%28p=p@entry=0x948000> <commands+288>, argc=argc@entry=4 <mailto:argc=argc@entry=4>, argv=argv@entry=0x7ffcd92199b0) <mailto:argv=argv@entry=0x7ffcd92199b0%29> at
perf.c:357
#16 0x0000000000437157 in handle_internal_command (argv=0x7ffcd92199b0, argc=4) at perf.c:419
#17 run_argv (argv=0x7ffcd9219720, argcp=0x7ffcd921972c) at perf.c:465 #18 main (argc=4, argv=0x7ffcd92199b0) at perf.c:609

Em Fri, Aug 05, 2016 at 06:58:12PM +0800, Wangnan (F) escreveu:

Quoted 60 lines

perf top comsumes too much memory than it need.

Using following commands:

  # yes '' > /dev/null
  # perf top -e raw_syscalls:sys_enter

System will quickly become unresponsive because of out of memory.

Using GDB I find two call stacks of malloc. See below.

[call stack 1]

#0 __GI___libc_malloc (bytes=140723951319552) at malloc.c:2841 #1 0x00000000004b7246 in memdup (src=0x7f515e04b054, len=68) at ../lib/string.c:29
#2 0x00000000004f9299 in hist_entry__init (sample_self=true, template=0x7ffcd9213a80, he=0xa37da50) at util/hist.c:401 #3 hist_entry__new (template=template@entry=0x7ffcd9213a80 <mailto:%28template=template@entry=0x7ffcd9213a80>, sample_self=sample_self@entry=true) <mailto:sample_self=sample_self@entry=true%29> at util/hist.c:458 #4 0x00000000004fa13f in hists__findnew_entry (hists=0x3549d30, hists=0x3549d30, al=0x7ffcd9213ca0, sample_self=true, entry=0x 7ffcd9213a80) at util/hist.c:544
#5 __hists__add_entry (hists=0x3549d30, al=0x7ffcd9213ca0, sym_parent=<optimized out>, bi=bi@entry=0x0 <mailto:bi=bi@entry=0x0>, mi=mi@entry=0x0 <mailto:mi=mi@entry=0x0>, sampl e=<optimized out>, sample_self=sample_self@entry=true <mailto:sample_self=sample_self@entry=true>, ops=ops@entry=0x0) <mailto:ops=ops@entry=0x0%29> at util/hist.c:600
#6 0x00000000004fa3d6 in hists__add_entry (sample_self=true, sample=<optimized out>, mi=0x0, bi=0x0, sym_parent=<optimized out

Quoted 1 line

, al=<optimized out>, hists=<optimized out>) at util/hist.c:611

#7 iter_add_single_normal_entry (iter=0x7ffcd9213ce0, al=<optimized out>) at util/hist.c:823
#8 0x00000000004fc3c5 in hist_entry_iter__add (iter=0x7ffcd9213ce0, al=0x7ffcd9213ca0, max_stack_depth=<optimized out>, arg=0x 7ffcd9214120) at util/hist.c:1030
#9 0x00000000004536d7 in perf_event__process_sample (machine=<optimized out>, sample=0x7ffcd9213d30, evsel=0x3549bb0, event=<o
ptimized out>, tool=0x7ffcd9214120) at builtin-top.c:800
#10 perf_top__mmap_read_idx (top=top@entry=0x7ffcd9214120 <mailto:%28top=top@entry=0x7ffcd9214120>, idx=idx@entry=0) <mailto:idx=idx@entry=0%29> at builtin-top.c:866
#11 0x00000000004559fd in perf_top__mmap_read (top=0x7ffcd9214120) at builtin-top.c:883
#12 __cmd_top (top=0x7ffcd9214120) at builtin-top.c:1018
#13 cmd_top (argc=<optimized out>, argv=<optimized out>, prefix=<optimized out>) at builtin-top.c:1344
#14 0x0000000000493561 in run_builtin (p=p@entry=0x948000 <mailto:%28p=p@entry=0x948000> <commands+288>, argc=argc@entry=4 <mailto:argc=argc@entry=4>, argv=argv@entry=0x7ffcd92199b0) <mailto:argv=argv@entry=0x7ffcd92199b0%29> at
perf.c:357
#15 0x0000000000437157 in handle_internal_command (argv=0x7ffcd92199b0, argc=4) at perf.c:419
#16 run_argv (argv=0x7ffcd9219720, argcp=0x7ffcd921972c) at perf.c:465 #17 main (argc=4, argv=0x7ffcd92199b0) at perf.c:609

Quoted 6 lines

[call stack 2]

#0 __GI___libc_malloc (bytes=140723951319456) at malloc.c:2841 #1 0x00000000005766de in trace_seq_init (s=0x7ffcd92139b0) at trace-seq.c:60 #2 0x00000000004f7047 in get_trace_output (he=0x7ffcd9213a80) at util/sort.c:584

Yeah, this allocates 4K, way too much, can you try with this patch, which amounts to a trace_seq_trim()?

tools/perf/util/sort.c +0 -0

index 947d21f38398..37ddcf57500f 100644

Quoted 69 lines

Em Fri, Aug 05, 2016 at 06:58:12PM +0800, Wangnan (F) escreveu:

Quoted 60 lines

perf top comsumes too much memory than it need.

Using following commands:

  # yes '' > /dev/null
  # perf top -e raw_syscalls:sys_enter

System will quickly become unresponsive because of out of memory.

Using GDB I find two call stacks of malloc. See below.

[call stack 1]

#0 __GI___libc_malloc (bytes=140723951319552) at malloc.c:2841 #1 0x00000000004b7246 in memdup (src=0x7f515e04b054, len=68) at ../lib/string.c:29
#2 0x00000000004f9299 in hist_entry__init (sample_self=true, template=0x7ffcd9213a80, he=0xa37da50) at util/hist.c:401 #3 hist_entry__new (template=template@entry=0x7ffcd9213a80 <mailto:%28template=template@entry=0x7ffcd9213a80>, sample_self=sample_self@entry=true) <mailto:sample_self=sample_self@entry=true%29> at util/hist.c:458 #4 0x00000000004fa13f in hists__findnew_entry (hists=0x3549d30, hists=0x3549d30, al=0x7ffcd9213ca0, sample_self=true, entry=0x 7ffcd9213a80) at util/hist.c:544
#5 __hists__add_entry (hists=0x3549d30, al=0x7ffcd9213ca0, sym_parent=<optimized out>, bi=bi@entry=0x0 <mailto:bi=bi@entry=0x0>, mi=mi@entry=0x0 <mailto:mi=mi@entry=0x0>, sampl e=<optimized out>, sample_self=sample_self@entry=true <mailto:sample_self=sample_self@entry=true>, ops=ops@entry=0x0) <mailto:ops=ops@entry=0x0%29> at util/hist.c:600
#6 0x00000000004fa3d6 in hists__add_entry (sample_self=true, sample=<optimized out>, mi=0x0, bi=0x0, sym_parent=<optimized out

Quoted 1 line

, al=<optimized out>, hists=<optimized out>) at util/hist.c:611

#7 iter_add_single_normal_entry (iter=0x7ffcd9213ce0, al=<optimized out>) at util/hist.c:823
#8 0x00000000004fc3c5 in hist_entry_iter__add (iter=0x7ffcd9213ce0, al=0x7ffcd9213ca0, max_stack_depth=<optimized out>, arg=0x 7ffcd9214120) at util/hist.c:1030
#9 0x00000000004536d7 in perf_event__process_sample (machine=<optimized out>, sample=0x7ffcd9213d30, evsel=0x3549bb0, event=<o
ptimized out>, tool=0x7ffcd9214120) at builtin-top.c:800
#10 perf_top__mmap_read_idx (top=top@entry=0x7ffcd9214120 <mailto:%28top=top@entry=0x7ffcd9214120>, idx=idx@entry=0) <mailto:idx=idx@entry=0%29> at builtin-top.c:866
#11 0x00000000004559fd in perf_top__mmap_read (top=0x7ffcd9214120) at builtin-top.c:883
#12 __cmd_top (top=0x7ffcd9214120) at builtin-top.c:1018
#13 cmd_top (argc=<optimized out>, argv=<optimized out>, prefix=<optimized out>) at builtin-top.c:1344
#14 0x0000000000493561 in run_builtin (p=p@entry=0x948000 <mailto:%28p=p@entry=0x948000> <commands+288>, argc=argc@entry=4 <mailto:argc=argc@entry=4>, argv=argv@entry=0x7ffcd92199b0) <mailto:argv=argv@entry=0x7ffcd92199b0%29> at
perf.c:357
#15 0x0000000000437157 in handle_internal_command (argv=0x7ffcd92199b0, argc=4) at perf.c:419
#16 run_argv (argv=0x7ffcd9219720, argcp=0x7ffcd921972c) at perf.c:465 #17 main (argc=4, argv=0x7ffcd92199b0) at perf.c:609

Quoted 5 lines

[call stack 2]
#0 __GI___libc_malloc (bytes=140723951319456) at malloc.c:2841 #1 0x00000000005766de in trace_seq_init (s=0x7ffcd92139b0) at trace-seq.c:60 #2 0x00000000004f7047 in get_trace_output (he=0x7ffcd9213a80) at util/sort.c:584

Yeah, this allocates 4K, way too much, can you try with this patch, which amounts to a trace_seq_trim()?

tools/perf/util/sort.c static char *get_trace_output(struct hist_entry *he) · line 593

Quoted 12 lines

tools/perf/util/sort.c +1 -1

index 947d21f38398..37ddcf57500f 100644
@@ -588,7 +588,7 @@ static char *get_trace_output(struct hist_entry *he)
  	} else {
  		pevent_event_info(&seq, evsel->tp_format, &rec);
  	}
-	return seq.buffer;
+	return realloc(seq.buffer, seq.len);
  }
  static int64_t

It works: from 1.8g/10s to 40m/10s, but unfortunately your patch is wrong: please use realloc(seq.buffer, seq.len + 1) because of the ending '\0' :)

In my experiment RSS continuously increases because I use raw_syscalls, which can result in too much entries to record in perf top because of the nature of argument list (garbage arguments are also considered by perf). It becomes much better if I use --fields to reduce the number of possible entries. However, theoretically perf will eventually consume all system memory, unless we carefully choose tracepoints and fields to make sure the possible entries is limited.