From: Eric Wong <e@yhbt.net>
To: meta@public-inbox.org
Subject: [PATCH 2/3] nntpd+imapd: detect unlinked msgmap
Date: Tue, 14 Jul 2020 02:14:31 +0000 [thread overview]
Message-ID: <20200714021432.11024-3-e@yhbt.net> (raw)
In-Reply-To: <20200714021432.11024-1-e@yhbt.net>
While it's even less common to experience a replaced
msgmap.sqlite3 file, BOFHs may do the darndest things. This is
another step towards reducing the number of needless wakeups
we need to do in long-lived read-only daemons.
---
lib/PublicInbox/Inbox.pm | 7 ++---
lib/PublicInbox/Msgmap.pm | 59 ++++++++++++++++++++-------------------
t/nntpd.t | 8 ++++++
3 files changed, 42 insertions(+), 32 deletions(-)
diff --git a/lib/PublicInbox/Inbox.pm b/lib/PublicInbox/Inbox.pm
index 02186dac..3d9754dc 100644
--- a/lib/PublicInbox/Inbox.pm
+++ b/lib/PublicInbox/Inbox.pm
@@ -31,7 +31,7 @@ sub cleanup_task () {
for my $ibx (values %$CLEANUP) {
my $again;
if ($have_devel_peek) {
- foreach my $f (qw(mm search)) {
+ foreach my $f (qw(search)) {
# we bump refcnt by assigning tmp, here:
my $tmp = $ibx->{$f} or next;
next if Devel::Peek::SvREFCNT($tmp) > 2;
@@ -47,7 +47,7 @@ sub cleanup_task () {
}
check_inodes($ibx);
if ($have_devel_peek) {
- $again ||= !!($ibx->{mm} || $ibx->{search});
+ $again ||= !!$ibx->{search};
}
$next->{"$ibx"} = $ibx if $again;
}
@@ -182,7 +182,6 @@ sub mm {
my ($self) = @_;
$self->{mm} ||= eval {
require PublicInbox::Msgmap;
- _cleanup_later($self);
my $dir = $self->{inboxdir};
if ($self->version >= 2) {
PublicInbox::Msgmap->new_file("$dir/msgmap.sqlite3");
@@ -409,7 +408,7 @@ sub unsubscribe_unlock {
sub check_inodes ($) {
my ($self) = @_;
- for (qw(over)) { # TODO: search, mm
+ for (qw(over mm)) { # TODO: search
$self->{$_}->check_inodes if $self->{$_};
}
}
diff --git a/lib/PublicInbox/Msgmap.pm b/lib/PublicInbox/Msgmap.pm
index aa07e344..e86fb854 100644
--- a/lib/PublicInbox/Msgmap.pm
+++ b/lib/PublicInbox/Msgmap.pm
@@ -13,6 +13,7 @@ use warnings;
use DBI;
use DBD::SQLite;
use File::Temp qw(tempfile);
+use PublicInbox::Over;
sub new {
my ($class, $git_dir, $writable) = @_;
@@ -24,29 +25,13 @@ sub new {
new_file($class, "$d/msgmap.sqlite3", $writable);
}
-sub dbh_new {
- my ($f, $writable) = @_;
- if ($writable && !-f $f) { # SQLite defaults mode to 0644, we want 0666
- open my $fh, '+>>', $f or die "failed to open $f: $!";
- }
- my $dbh = DBI->connect("dbi:SQLite:dbname=$f",'','', {
- AutoCommit => 1,
- RaiseError => 1,
- PrintError => 0,
- ReadOnly => !$writable,
- sqlite_use_immediate_transaction => 1,
- });
- $dbh;
-}
-
sub new_file {
- my ($class, $f, $writable) = @_;
- return if !$writable && !-r $f;
+ my ($class, $f, $rw) = @_;
+ return if !$rw && !-r $f;
- my $dbh = dbh_new($f, $writable);
- my $self = bless { dbh => $dbh }, $class;
-
- if ($writable) {
+ my $self = bless { filename => $f }, $class;
+ my $dbh = $self->{dbh} = PublicInbox::Over::dbh_new($self, $rw);
+ if ($rw) {
create_tables($dbh);
# TRUNCATE reduces I/O compared to the default (DELETE)
@@ -70,7 +55,6 @@ sub tmp_clone {
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} = $$;
close $fh or die "failed to close $fn: $!";
$tmp;
@@ -246,28 +230,28 @@ sub mid_set {
sub DESTROY {
my ($self) = @_;
delete $self->{dbh};
- my $f = delete $self->{tmp_name};
- if (defined $f && $self->{pid} == $$) {
+ my $f = $self->{filename};
+ if (($self->{pid} // 0) == $$) {
unlink $f or warn "failed to unlink $f: $!\n";
}
}
sub atfork_parent {
my ($self) = @_;
- my $f = $self->{tmp_name} or die "not a temporary clone\n";
+ $self->{pid} or die "not a temporary clone\n";
delete $self->{dbh} and die "tmp_clone dbh not prepared for parent";
- my $dbh = $self->{dbh} = dbh_new($f, 1);
+ my $dbh = $self->{dbh} = PublicInbox::Over::dbh_new($self, 1);
$dbh->do('PRAGMA synchronous = OFF');
}
sub atfork_prepare {
my ($self) = @_;
- my $f = $self->{tmp_name} or die "not a temporary clone\n";
+ $self->{pid} or die "not a temporary clone\n";
$self->{pid} == $$ or
die "BUG: atfork_prepare not called from $self->{pid}\n";
$self->{dbh} or die "temporary clone not open\n";
# must clobber prepared statements
- %$self = (tmp_name => $f, pid => $$);
+ %$self = (filename => $self->{filename}, pid => $$);
}
sub skip_artnum {
@@ -296,4 +280,23 @@ sub skip_artnum {
}
}
+sub check_inodes {
+ my ($self) = @_;
+ # no filename if in-:memory:
+ my $f = $self->{dbh}->sqlite_db_filename // return;
+ if (my @st = stat($f)) { # did st_dev, st_ino change?
+ my $st = pack('dd', $st[0], $st[1]);
+ if ($st ne ($self->{st} // $st)) {
+ my $tmp = eval { ref($self)->new_file($f) };
+ if ($@) {
+ warn "E: DBI->connect($f): $@\n";
+ } else {
+ %$self = %$tmp;
+ }
+ }
+ } else {
+ warn "W: stat $f: $!\n";
+ }
+}
+
1;
diff --git a/t/nntpd.t b/t/nntpd.t
index 28008ec1..954e6e75 100644
--- a/t/nntpd.t
+++ b/t/nntpd.t
@@ -14,6 +14,7 @@ use Net::NNTP;
use Sys::Hostname;
use POSIX qw(_exit);
use Digest::SHA;
+use_ok 'PublicInbox::Msgmap';
# FIXME: make easier to test both versions
my $version = $ENV{PI_TEST_VERSION} || 1;
@@ -341,6 +342,13 @@ Date: Fri, 02 Oct 1993 00:00:00 +0000
'article did not exist');
$im->add($ex);
$im->done;
+ {
+ my $f = $ibx->mm->{filename};
+ my $tmp = "$tmpdir/tmp.sqlite3";
+ $ibx->mm->{dbh}->sqlite_backup_to_file($tmp);
+ delete $ibx->{mm};
+ rename($tmp, $f) or BAIL_OUT "rename($tmp, $f): $!";
+ }
ok(run_script([qw(-index --reindex -c), $ibx->{inboxdir}],
undef, $noerr), '-compacted');
select(undef, undef, undef, $fast_idle ? 0.1 : 2.1);
next prev parent reply other threads:[~2020-07-14 2:14 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-14 2:14 [PATCH 0/3] avoid msgmap reopens in long-lived processes Eric Wong
2020-07-14 2:14 ` [PATCH 1/3] over: unset sqlite_unicode attribute Eric Wong
2020-07-14 2:14 ` Eric Wong [this message]
2020-07-14 2:14 ` [PATCH 3/3] over+msgmap: do not store filename after DBI->connect Eric Wong
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