lei: micro-optimize startup time

We'll use lower-level Socket and avoid IO::Socket::UNIX,
use Cwd::fastcwd(*), avoid IO::Handle->autoflush by
using the select operator, and reuse buffer for reading
the socket while avoiding unnecessary $/ localization
in a tiny script.

All these things adds up to ~5-10 ms savings on my loaded
system.

(*) caveats about fastcwd won't apply since lei won't work
    in removed directories.

diff --git a/lib/PublicInbox/LEI.pm b/lib/PublicInbox/LEI.pm
index f5824c59ad9879a43d74101e3e22ae3be7c0fd14..5399fadeefa641094ee4aeab04d8c515f4557192 100644 (file)
--- a/lib/PublicInbox/LEI.pm
+++ b/lib/PublicInbox/LEI.pm
@@ -10,9 +10,9 @@ use strict;
 use v5.10.1;
 use parent qw(PublicInbox::DS);
 use Getopt::Long ();
+use Socket qw(AF_UNIX SOCK_STREAM pack_sockaddr_un);
 use Errno qw(EAGAIN ECONNREFUSED ENOENT);
 use POSIX qw(setsid);
-use IO::Socket::UNIX;
 use IO::Handle ();
 use Sys::Syslog qw(syslog openlog);
 use PublicInbox::Config;
@@ -585,18 +585,17 @@ sub noop {}
 # lei(1) calls this when it can't connect
 sub lazy_start {
        my ($path, $err) = @_;
+       require IO::FDPass; # require this early so caller sees it
        if ($err == ECONNREFUSED) {
                unlink($path) or die "unlink($path): $!";
        } elsif ($err != ENOENT) {
+               $! = $err; # allow interpolation to stringify in die
                die "connect($path): $!";
        }
-       require IO::FDPass;
        umask(077) // die("umask(077): $!");
-       my $l = IO::Socket::UNIX->new(Local => $path,
-                                       Listen => 1024,
-                                       Type => SOCK_STREAM) or
-               $err = $!;
-       $l or return die "bind($path): $err";
+       socket(my $l, AF_UNIX, SOCK_STREAM, 0) or die "socket: $!";
+       bind($l, pack_sockaddr_un($path)) or die "bind($path): $!";
+       listen($l, 1024) or die "listen $!";
        my @st = stat($path) or die "stat($path): $!";
        my $dev_ino_expect = pack('dd', $st[0], $st[1]); # dev+ino
        pipe(my ($eof_r, $eof_w)) or die "pipe: $!";

diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index c236c589e2e838302e333ecca66704f70c226270..338e760c5be8ec24d084804a3be9771616b645d3 100644 (file)
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -261,6 +261,7 @@ sub run_script ($;$$) {
                my $orig_io = _prepare_redirects($fhref);
                _run_sub($sub, $key, \@argv);
                _undo_redirects($orig_io);
+               select STDOUT;
        }
 
        # slurp the redirects back into user-supplied strings

diff --git a/script/lei b/script/lei
index e59e4316785639960b6f708693b9849c46c2db61..2b041fb4636624e4b81af3aa3c5ef4576ac00834 100755 (executable)
--- a/script/lei
+++ b/script/lei
@@ -3,8 +3,7 @@
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 use strict;
 use v5.10.1;
-use Cwd qw(cwd);
-use IO::Socket::UNIX;
+use Socket qw(AF_UNIX SOCK_STREAM pack_sockaddr_un);
 
 if (eval { require IO::FDPass; 1 }) { # use daemon to reduce load time
        my $path = do {
@@ -13,14 +12,15 @@ if (eval { require IO::FDPass; 1 }) { # use daemon to reduce load time
                        require File::Spec;
                        $runtime_dir = File::Spec->tmpdir."/lei-$<";
                }
-               unless (-d $runtime_dir && -w _) {
+               unless (-d $runtime_dir) {
                        require File::Path;
                        File::Path::mkpath($runtime_dir, 0, 0700);
                }
                "$runtime_dir/sock";
        };
-       my $sock = IO::Socket::UNIX->new(Peer => $path, Type => SOCK_STREAM);
-       unless ($sock) { # start the daemon if not started
+       my $addr = pack_sockaddr_un($path);
+       socket(my $sock, AF_UNIX, SOCK_STREAM, 0) or die "socket: $!";
+       unless (connect($sock, $addr)) { # start the daemon if not started
                my $err = $! + 0;
                my $env = { PERL5LIB => join(':', @INC) };
                my $cmd = [ $^X, qw[-MPublicInbox::LEI
@@ -31,13 +31,14 @@ if (eval { require IO::FDPass; 1 }) { # use daemon to reduce load time
                warn "lei-daemon exited with \$?=$?\n" if $?;
 
                # try connecting again anyways, unlink+bind may be racy
-               $sock = IO::Socket::UNIX->new(Peer => $path,
-                                               Type => SOCK_STREAM) // die
+               connect($sock, $addr) or die
                        "connect($path): $! (after attempted daemon start)";
        }
-       my $pwd = $ENV{PWD};
-       my $cwd = cwd();
-       if ($pwd) { # prefer ENV{PWD} if it's a symlink to real cwd
+       require Cwd;
+       my $cwd = Cwd::fastcwd() // die "fastcwd: $!";
+       my $pwd = $ENV{PWD} // '';
+       if ($pwd eq $cwd) { # likely, all good
+       } elsif ($pwd) { # prefer ENV{PWD} if it's a symlink to real cwd
                my @st_cwd = stat($cwd) or die "stat(cwd=$cwd): $!\n";
                my @st_pwd = stat($pwd);
                # make sure st_dev/st_ino match for {PWD} to be valid
@@ -47,16 +48,16 @@ if (eval { require IO::FDPass; 1 }) { # use daemon to reduce load time
                $pwd = $cwd;
        }
        local $ENV{PWD} = $pwd;
-       $sock->autoflush(1);
-       IO::FDPass::send(fileno($sock), $_) for (0..2);
        my $buf = "$$\0\0>" . join("]\0[", @ARGV) . "\0\0>";
        while (my ($k, $v) = each %ENV) { $buf .= "$k=$v\0" }
        $buf .= "\0\0";
+       select $sock;
+       $| = 1; # unbuffer selected $sock
+       IO::FDPass::send(fileno($sock), $_) for (0..2);
        print $sock $buf or die "print(sock, buf): $!";
-       local $/ = "\n";
-       while (my $line = <$sock>) {
-               $line =~ /\Aexit=([0-9]+)\n\z/ and exit($1 + 0);
-               die $line;
+       while ($buf = <$sock>) {
+               $buf =~ /\Aexit=([0-9]+)\n\z/ and exit($1 + 0);
+               die $buf;
        }
 } else { # for systems lacking IO::FDPass
        require PublicInbox::LEI;