Re: Memory issues

jm a écrit :

Modifying a little bit again the script, and checking execution with
ltrace, I observed malloc is called 1871 times when free is just called
922 times.
Isn't it an issue?

and did:

ltrace perl essai.pl 2>&1 | grep 'malloc\|free\|realloc' | perl
observe_malloc_free.pl > memory.log

with observe_malloc_free.pl in mail bottom.

Hereafter, this result of memory leaks:

1 NULL is freed, but thats not a memory leak!

the rest can be read like this:
7 10 Mbytes data are not freed.
1 13 Mbytes data is not freed
8272 4 bytes data are not freed
9843 4080 bytes data are not freed

but I still do not know why...

/tmp$ cat memory.log | sed 's/.*=>//g' | sort | uniq -c
7 10
10 100
7 10000004
22 11
4 112
10 116
1 1192
26 12
1 124
4 128
12 13
1 131716
1 13334528
13 14
3 140
6 15
28 16
9 17
14 18
8 19
19 2
14 20
1 2048
6 21
5 22
3 23
230 24
1 240
6 25
7 256
4 27
1 2712
143 28
4 3
2 30
1 31
125 32
2 33
2 34
1 36
8272 4
3 40
1 4048
1 4064
9843 4080
8 4096
2 4373
1 44
1 45
78 48
1 49156
2 496
72 5
1 50
1 512
65 52
50 56
1 58
6 6
1 628
1 635
13 64
18 7
1 76
45 8
1 80
1 8080
2 84
4 88
74 9
1 98
1 freeing not allocated memory : NULL :



--- scipt ---------------------------
sub aa($)
{
my ($d) = @_;
$$d =~ s/x(.....)/$1y/g ;
$$d =~ s/x(.....)/$1z/g ;
$$d =~ s/x(.....)/$1a/g ;
$$d =~ s/x(.....)/$1b/g ;
$$d =~ s/x(.....)/$1c/g ;
return $d;
}

sub ab($)
{
my ($d) = @_;
$$d =~ s/a(.....)/$1y/g ;
$$d =~ s/b(.....)/$1z/g ;
$$d =~ s/c(.....)/$1a/g ;
$$d =~ s/y(.....)/$1b/g ;
$$d =~ s/z(.....)/$1c/g ;
return $d;
}


my $s= 'x' x (1000*1000*10) ;
$s .= "\x{1234}" ;
my $c = \$s;
print length($$c) ."\n" ;
my $v = qx( ps v $$ );
print "$v\n" ;
$c = aa($c);
print length($$c) ."\n" ;
my $v = qx( ps v $$ );
print "$v\n" ;
$c = aa($c);
$c = aa($c);
$c = aa($c);
$c = aa($c);
$c = aa($c);
print length($$c) ."\n" ;
my $v = qx( ps v $$ );
print "$v\n" ;
$c = ab($c);
$c = ab($c);
$c = ab($c);
$c = ab($c);
$c = ab($c);
print length($$c) ."\n" ;
my $v = qx( ps v $$ );
print "$v\n" ;
$c = ab($c);
$c = ab($c);
$c = ab($c);
$c = ab($c);
$c = ab($c);
print length($$c) ."\n" ;
my $v = qx( ps v $$ );
print "$v\n" ;

-- observe...pl --------------------------

my %hash = ();


while (<>)
{
my $line = $_;
#print "jmg:" . $line;
if ( $line =~ m/malloc\(([0-9]*)\).*= *([0-9xa-fNUL]*)/ )
{
my $size = $1;
my $ad = $2;
#print "malloc : $1 : $2 : \n" ;
if ( defined ( $hash{$ad}) )
{
print "redundant malloc : $1 : $2 : \n" ;
}
$hash{$ad} = $size;
}
elsif ( $line =~ m/realloc\(([0-9xa-fNUL]*) *, *([0-9]*)\).*=
*([0-9xa-fNUL]*)/ )
{
my $adp = $1;
my $size = $2;
my $ad = $3;


if ( not defined ( $hash{$adp}) )
{
print "realloc not allocated memory : $adp : \n" ;
}
delete $hash{$adp} ;

#print "malloc : $1 : $2 : \n" ;
if ( defined ( $hash{$ad}) )
{
print "redundant malloc : $size : $ad : \n" ;
}
$hash{$ad} = $size;
}
elsif ( $line =~ m/free\(([0-9xa-fNUL]*)/ )
{
my $ad = $1;
#print "free : $1 : \n" ;
if ( not defined ( $hash{$ad}) )
{
print "freeing not allocated memory : $1 : \n" ;
}
delete $hash{$ad} ;
}
else
{
print "???:" . $line;
}

}

foreach my $key ( keys ( %hash) )
{
print $key . ' => ' . $hash{$key} . "\n" ;
}
.