hl_mod: don't memoize highlight::codeGenerator objects

Making them immortal doesn't seem worth it, since doing immortal
allocations after process startup leads to fragmentation.  While
the allocations made by highlight are small, those small
allocations can break up contiguous regions and prevent
consolidation by the malloc implementation.

Since instantiating code generators doesn't seem too expensive,
just use and delete them ASAP.

diff --git a/lib/PublicInbox/HlMod.pm b/lib/PublicInbox/HlMod.pm
index 9016db3a03fc949eb0756d20f02037e6a8d58230..f42ece80ededc4a04f06f453170c7320aaf94391 100644 (file)
--- a/lib/PublicInbox/HlMod.pm
+++ b/lib/PublicInbox/HlMod.pm
@@ -14,7 +14,7 @@
 # wrapper for SWIG-generated highlight.pm bindings
 package PublicInbox::HlMod;
 use strict;
-use warnings;
+use v5.10.1;
 use highlight; # SWIG-generated stuff
 use PublicInbox::Hval qw(src_escape ascii_html);
 my $hl;
@@ -54,8 +54,7 @@ sub _parse_filetypes ($) {
        (\%ext2lang, \@shebang);
 }
 
-# We only need one instance, so we don't need to do
-# highlight::CodeGenerator::deleteInstance
+# We only need one instance
 sub new {
        my ($class) = @_;
        $hl ||= do {
@@ -95,33 +94,26 @@ sub do_hl {
 sub do_hl_lang {
        my ($self, $str, $lang) = @_;
 
-       my $dir = $self->{-dir};
        my $langpath;
-
        if (defined $lang) {
-               $langpath = $dir->getLangPath("$lang.lang") or return;
-               $lang = undef unless -f $langpath
-       }
-       unless (defined $lang) {
-               $lang = _shebang2lang($self, $str) or return;
-               $langpath = $dir->getLangPath("$lang.lang") or return;
-               return unless -f $langpath
+               $langpath = $self->{-dir}->getLangPath("$lang.lang") or return;
+               undef $lang unless -f $langpath;
        }
-       my $gen = $self->{$langpath} ||= do {
-               my $g = highlight::CodeGenerator::getInstance($highlight::HTML);
-               $g->setFragmentCode(1); # generate html fragment
+       $lang //= _shebang2lang($self, $str) // return;
+       $langpath = $self->{-dir}->getLangPath("$lang.lang") or return;
+       return unless -f $langpath;
 
-               # whatever theme works
-               my $themepath = $dir->getThemePath('print.theme');
-               $g->initTheme($themepath);
-               $g->loadLanguage($langpath);
-               $g->setEncoding('utf-8');
-               $g;
-       };
+       my $g = highlight::CodeGenerator::getInstance($highlight::HTML);
+       $g->setFragmentCode(1); # generate html fragment
 
+       # whatever theme works
+       $g->initTheme($self->{-dir}->getThemePath('print.theme'));
+       $g->loadLanguage($langpath);
+       $g->setEncoding('utf-8');
        # we assume $$str is valid UTF-8, but the SWIG binding doesn't
        # know that, so ensure it's marked as UTF-8 even if it isnt...
-       my $out = $gen->generateString($$str);
+       my $out = $g->generateString($$str);
+       highlight::CodeGenerator::deleteInstance($g);
        utf8::decode($out);
        src_escape($out);
        \$out;

diff --git a/t/hl_mod.t b/t/hl_mod.t
index 96878d5191dfa29197ebb8dc616c3a6a2c17b196..a88f6c0372bd2d1fcbbc0cd5bba482b3c22b37c5 100644 (file)
--- a/t/hl_mod.t
+++ b/t/hl_mod.t
@@ -3,8 +3,7 @@
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 use strict; use v5.10.1; use PublicInbox::TestCommon; use IO::Handle; # ->autoflush
 use Fcntl qw(:seek);
-eval { require highlight } or
-       plan skip_all => "failed to load highlight.pm for $0";
+require_mods 'highlight';
 use_ok 'PublicInbox::HlMod';
 my $hls = PublicInbox::HlMod->new;
 ok($hls, 'initialized OK');