-# Copyright (C) 2015-2018 all contributors <meta@public-inbox.org>
+# Copyright (C) 2015-2020 all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
# bidirectional Message-ID <-> Article Number mapping for the NNTP
if ($writable) {
create_tables($dbh);
+
+ # TRUNCATE reduces I/O compared to the default (DELETE)
+ $dbh->do('PRAGMA journal_mode = TRUNCATE');
+
$dbh->begin_work;
$self->created_at(time) unless $self->created_at;
- my (undef, $max) = $self->minmax();
- $max ||= 0;
+ my $max = $self->max // 0;
$self->num_highwater($max);
$dbh->commit;
}
$self->{dbh}->sqlite_backup_to_file($fn);
my $tmp = ref($self)->new_file($fn, 1);
$tmp->{dbh}->do('PRAGMA synchronous = OFF');
+ $tmp->{dbh}->do('PRAGMA journal_mode = MEMORY');
$tmp->{tmp_name} = $fn; # SQLite won't work if unlinked, apparently
$tmp->{pid} = $$;
close $fh or die "failed to close $fn: $!";
$sth->fetchrow_array;
}
+sub max {
+ my $sth = $_[0]->{dbh}->prepare_cached('SELECT MAX(num) FROM msgmap',
+ undef, 1);
+ $sth->execute;
+ $sth->fetchrow_array;
+}
+
sub minmax {
- my ($self) = @_;
- my $dbh = $self->{dbh};
# breaking MIN and MAX into separate queries speeds up from 250ms
# to around 700us with 2.7million messages.
- my $sth = $dbh->prepare_cached('SELECT MIN(num) FROM msgmap', undef, 1);
- $sth->execute;
- my $min = $sth->fetchrow_array;
- $sth = $dbh->prepare_cached('SELECT MAX(num) FROM msgmap', undef, 1);
+ my $sth = $_[0]->{dbh}->prepare_cached('SELECT MIN(num) FROM msgmap',
+ undef, 1);
$sth->execute;
- ($min, $sth->fetchrow_array);
+ ($sth->fetchrow_array, max($_[0]));
}
sub mid_delete {