]> Sergey Matveev's repositories - public-inbox.git/blobdiff - lib/PublicInbox/Xapcmd.pm
xcpdb: support resharding v2 repos
[public-inbox.git] / lib / PublicInbox / Xapcmd.pm
index 5d8c35f4e750a5bcdac94a2ee7f703fed7e4776d..e1c6fe3a9c9326a14d1dde5f31d31a811884f843 100644 (file)
@@ -17,34 +17,66 @@ our @COMPACT_OPT = qw(jobs|j=i quiet|q blocksize|b=s no-full|n fuller|F);
 
 sub commit_changes ($$$) {
        my ($ibx, $tmp, $opt) = @_;
-
+       my $new_parts = $opt->{reshard};
        my $reindex = $opt->{reindex};
        my $im = $ibx->importer(0);
        $im->lock_acquire if !$opt->{-coarse_lock};
 
        $SIG{INT} or die 'BUG: $SIG{INT} not handled';
+       my @old_part;
 
        while (my ($old, $new) = each %$tmp) {
-               my @st = stat($old) or die "failed to stat($old): $!\n";
+               my @st = stat($old);
+               if (!@st && !defined($opt->{reshard})) {
+                       die "failed to stat($old): $!";
+               }
 
                my $over = "$old/over.sqlite3";
                if (-f $over) { # only for v1, v2 over is untouched
+                       defined $new or die "BUG: $over exists when culling v2";
                        $over = PublicInbox::Over->new($over);
                        my $tmp_over = "$new/over.sqlite3";
                        $over->connect->sqlite_backup_to_file($tmp_over);
                        $over = undef;
                }
-               chmod($st[2] & 07777, $new) or die "chmod $old: $!\n";
 
+               if (!defined($new)) { # culled partition
+                       push @old_part, $old;
+                       next;
+               }
+
+               if (@st) {
+                       chmod($st[2] & 07777, $new) or die "chmod $old: $!\n";
+                       rename($old, "$new/old") or
+                                       die "rename $old => $new/old: $!\n";
+               }
                # Xtmpdir->DESTROY won't remove $new after this:
-               rename($old, "$new/old") or die "rename $old => $new/old: $!\n";
                rename($new, $old) or die "rename $new => $old: $!\n";
-               my $prev = "$old/old";
-               remove_tree($prev) or die "failed to remove $prev: $!\n";
+               if (@st) {
+                       my $prev = "$old/old";
+                       remove_tree($prev) or
+                               die "failed to remove $prev: $!\n";
+               }
        }
+       remove_tree(@old_part);
        $tmp->done;
        if (!$opt->{-coarse_lock}) {
                $opt->{-skip_lock} = 1;
+
+               if ($im->can('count_partitions')) {
+                       my $pr = $opt->{-progress};
+                       my $n = $im->count_partitions;
+                       if (defined $new_parts && $n != $new_parts) {
+                               die
+"BUG: counted $n partitions after repartioning to $new_parts";
+                       }
+                       my $prev = $im->{partitions};
+                       if ($pr && $prev != $n) {
+                               $pr->("partition count changed: $prev => $n\n");
+                               $im->{partitions} = $n;
+                       }
+               }
+
                PublicInbox::Admin::index_inbox($ibx, $opt);
                # implicit lock_release
        } else {
@@ -139,32 +171,59 @@ sub run {
        my $tmp = PublicInbox::Xtmpdirs->new;
        my $v = $ibx->{version} ||= 1;
        my @q;
+       my $new_parts = $opt->{reshard};
+       if (defined $new_parts && $new_parts <= 0) {
+               die "--reshard must be a positive number\n";
+       }
 
        # we want temporary directories to be as deep as possible,
        # so v2 partitions can keep "xap$SCHEMA_VERSION" on a separate FS.
        if ($v == 1) {
+               if (defined $new_parts) {
+                       warn
+"--reshard=$new_parts ignored for v1 $ibx->{mainrepo}\n";
+               }
                my $old_parent = dirname($old);
                same_fs_or_die($old_parent, $old);
                my $v = PublicInbox::Search::SCHEMA_VERSION();
-               $tmp->{$old} = tempdir("xapian$v-XXXXXXXX", DIR => $old_parent);
-               push @q, [ $old, $tmp->{$old} ];
+               my $wip = tempdir("xapian$v-XXXXXXXX", DIR => $old_parent);
+               $tmp->{$old} = $wip;
+               push @q, [ $old, $wip ];
        } else {
                opendir my $dh, $old or die "Failed to opendir $old: $!\n";
+               my @old_parts;
                while (defined(my $dn = readdir($dh))) {
                        if ($dn =~ /\A[0-9]+\z/) {
-                               my $tmpl = "$dn-XXXXXXXX";
-                               my $dst = tempdir($tmpl, DIR => $old);
-                               same_fs_or_die($old, $dst);
-                               my $cur = "$old/$dn";
-                               push @q, [ $cur, $dst ];
-                               $tmp->{$cur} = $dst;
+                               push @old_parts, $dn;
                        } elsif ($dn eq '.' || $dn eq '..') {
                        } elsif ($dn =~ /\Aover\.sqlite3/) {
                        } else {
                                warn "W: skipping unknown dir: $old/$dn\n"
                        }
                }
-               die "No Xapian parts found in $old\n" unless @q;
+               die "No Xapian parts found in $old\n" unless @old_parts;
+
+               my ($src, $max_part);
+               if (!defined($new_parts) || $new_parts == scalar(@old_parts)) {
+                       # 1:1 copy
+                       $max_part = scalar(@old_parts) - 1;
+               } else {
+                       # M:N copy
+                       $max_part = $new_parts - 1;
+                       $src = [ map { "$old/$_" } @old_parts ];
+               }
+               foreach my $dn (0..$max_part) {
+                       my $tmpl = "$dn-XXXXXXXX";
+                       my $wip = tempdir($tmpl, DIR => $old);
+                       same_fs_or_die($old, $wip);
+                       my $cur = "$old/$dn";
+                       push @q, [ $src // $cur , $wip ];
+                       $tmp->{$cur} = $wip;
+               }
+               # mark old parts to be unlinked
+               if ($src) {
+                       $tmp->{$_} ||= undef for @$src;
+               }
        }
        my $im = $ibx->importer(0);
        my $max = $opt->{jobs} || scalar(@q);
@@ -245,12 +304,74 @@ sub compact ($$) {
        }
 }
 
+sub cpdb_loop ($$$;$$) {
+       my ($src, $dst, $pr_data, $cur_part, $new_parts) = @_;
+       my ($pr, $fmt, $nr, $pfx);
+       if ($pr_data) {
+               $pr = $pr_data->{pr};
+               $fmt = $pr_data->{fmt};
+               $nr = \($pr_data->{nr});
+               $pfx = $pr_data->{pfx};
+       }
+
+       my ($it, $end);
+       do {
+               eval {
+                       $it = $src->postlist_begin('');
+                       $end = $src->postlist_end('');
+               };
+       } while (cpdb_retryable($src, $pfx));
+
+       do {
+               eval {
+                       for (; $it != $end; $it++) {
+                               my $docid = $it->get_docid;
+                               if (defined $new_parts) {
+                                       my $dst_part = $docid % $new_parts;
+                                       next if $dst_part != $cur_part;
+                               }
+                               my $doc = $src->get_document($docid);
+                               $dst->replace_document($docid, $doc);
+                               if ($pr_data && !(++$$nr  & 1023)) {
+                                       $pr->(sprintf($fmt, $$nr));
+                               }
+                       }
+
+                       # unlike copydatabase(1), we don't copy spelling
+                       # and synonym data (or other user metadata) since
+                       # the Perl APIs don't expose iterators for them
+                       # (and public-inbox does not use those features)
+               };
+       } while (cpdb_retryable($src, $pfx));
+}
+
 # Like copydatabase(1), this is horribly slow; and it doesn't seem due
 # to the overhead of Perl.
 sub cpdb ($$) {
        my ($args, $opt) = @_;
        my ($old, $new) = @$args;
-       my $src = Search::Xapian::Database->new($old);
+       my ($src, $cur_part);
+       my $new_parts;
+       if (ref($old) eq 'ARRAY') {
+               ($cur_part) = ($new =~ m!xap[0-9]+/([0-9]+)\b!);
+               defined $cur_part or
+                       die "BUG: could not extract partition # from $new";
+               $new_parts = $opt->{reshard};
+               defined $new_parts or die 'BUG: got array src w/o --partition';
+
+               # repartitioning, M:N copy means have full read access
+               foreach (@$old) {
+                       if ($src) {
+                               my $sub = Search::Xapian::Database->new($_);
+                               $src->add_database($sub);
+                       } else {
+                               $src = Search::Xapian::Database->new($_);
+                       }
+               }
+       } else {
+               $src = Search::Xapian::Database->new($old);
+       }
+
        my ($xtmp, $tmp);
        if ($opt->{compact}) {
                my $newdir = dirname($new);
@@ -266,10 +387,9 @@ sub cpdb ($$) {
        # of other bugs:
        my $creat = Search::Xapian::DB_CREATE();
        my $dst = Search::Xapian::WritableDatabase->new($tmp, $creat);
-       my ($it, $end);
-       my ($nr, $tot, $fmt); # progress output
        my $pr = $opt->{-progress};
        my $pfx = $opt->{-progress_pfx} = progress_pfx($new);
+       my $pr_data = { pr => $pr, pfx => $pfx, nr => 0 } if $pr;
 
        do {
                eval {
@@ -284,38 +404,39 @@ sub cpdb ($$) {
                                        $dst->set_metadata('indexlevel', $l);
                                }
                        }
-
-                       $it = $src->postlist_begin('');
-                       $end = $src->postlist_end('');
-                       if ($pr) {
-                               $nr = 0;
-                               $tot = $src->get_doccount;
-                               $fmt = "$pfx % ".length($tot)."u/$tot\n";
-                               $pr->("$pfx copying $tot documents\n");
-                       }
-               };
-       } while (cpdb_retryable($src, $pfx));
-
-       do {
-               eval {
-                       while ($it != $end) {
-                               my $docid = $it->get_docid;
-                               my $doc = $src->get_document($docid);
-                               $dst->replace_document($docid, $doc);
-                               $it->inc;
-                               if ($pr && !(++$nr & 1023)) {
-                                       $pr->(sprintf($fmt, $nr));
+                       if ($pr_data) {
+                               my $tot = $src->get_doccount;
+
+                               # we can only estimate when repartitioning,
+                               # because removed spam causes slight imbalance
+                               my $est = '';
+                               if (defined $cur_part && $new_parts > 1) {
+                                       $tot = int($tot/$new_parts);
+                                       $est = 'around ';
                                }
+                               my $fmt = "$pfx % ".length($tot)."u/$tot\n";
+                               $pr->("$pfx copying $est$tot documents\n");
+                               $pr_data->{fmt} = $fmt;
+                               $pr_data->{total} = $tot;
                        }
-
-                       # unlike copydatabase(1), we don't copy spelling
-                       # and synonym data (or other user metadata) since
-                       # the Perl APIs don't expose iterators for them
-                       # (and public-inbox does not use those features)
                };
        } while (cpdb_retryable($src, $pfx));
 
-       $pr->(sprintf($fmt, $nr)) if $pr;
+       if (defined $new_parts) {
+               # we rely on document IDs matching NNTP article number,
+               # so we can't have the combined DB support rewriting
+               # document IDs.  Thus we iterate through each shard
+               # individually.
+               $src = undef;
+               foreach (@$old) {
+                       my $old = Search::Xapian::Database->new($_);
+                       cpdb_loop($old, $dst, $pr_data, $cur_part, $new_parts);
+               }
+       } else {
+               cpdb_loop($src, $dst, $pr_data);
+       }
+
+       $pr->(sprintf($pr_data->{fmt}, $pr_data->{nr})) if $pr;
        return unless $xtmp;
 
        $src = $dst = undef; # flushes and closes
@@ -360,6 +481,7 @@ sub DESTROY {
        my $owner_pid = delete $owner{"$self"} or return;
        return if $owner_pid != $$;
        foreach my $new (values %$self) {
+               defined $new or next; # may be undef if repartitioning
                remove_tree($new) unless -d "$new/old";
        }
        done($self);