xcpdb: use fine-grained locking

Copying an entire Xapian DB takes a long time, so update our
reindexing code to support partial reindexing, snapshot the
pre-copydatabase git revisions, perform the lengthy copy,
and do a partial reindex when the copy + renames are done.

diff --git a/lib/PublicInbox/Admin.pm b/lib/PublicInbox/Admin.pm
index 94f47abbc6a2aa3a73203364f5c38b6e2fb7b060..34aa3129f5228de6166f7b5d84261cdea0631e8a 100644 (file)
--- a/lib/PublicInbox/Admin.pm
+++ b/lib/PublicInbox/Admin.pm
@@ -141,7 +141,7 @@ sub index_inbox {
        if (ref($ibx) && ($ibx->{version} || 1) == 2) {
                eval { require PublicInbox::V2Writable };
                die "v2 requirements not met: $@\n" if $@;
-               my $v2w = eval {
+               my $v2w = eval { $ibx->importer(0) } || eval {
                        PublicInbox::V2Writable->new($ibx, {nproc=>$jobs});
                };
                if (defined $jobs) {

diff --git a/lib/PublicInbox/SearchIdx.pm b/lib/PublicInbox/SearchIdx.pm
index 114420e4b82a2b4f71fce48c8538d7ede36e9ea2..0aeeb6bc544acce630adacd28e6b063e8295b6be 100644 (file)
--- a/lib/PublicInbox/SearchIdx.pm
+++ b/lib/PublicInbox/SearchIdx.pm
@@ -542,8 +542,10 @@ sub do_cat_mail {
        $@ ? undef : $mime;
 }
 
+# called by public-inbox-index
 sub index_sync {
        my ($self, $opts) = @_;
+       delete $self->{lock_path} if $opts->{-skip_lock};
        $self->{-inbox}->with_umask(sub { $self->_index_sync($opts) })
 }
 
@@ -692,6 +694,12 @@ sub _last_x_commit {
        $lx;
 }
 
+sub reindex_from ($$) {
+       my ($reindex, $last_commit) = @_;
+       return $last_commit unless $reindex;
+       ref($reindex) eq 'HASH' ? $reindex->{from} : '';
+}
+
 # indexes all unindexed messages (v1 only)
 sub _index_sync {
        my ($self, $opts) = @_;
@@ -705,7 +713,7 @@ sub _index_sync {
        do {
                $xlog = undef;
                $last_commit = _last_x_commit($self, $mm);
-               $lx = $opts->{reindex} ? '' : $last_commit;
+               $lx = reindex_from($opts->{reindex}, $last_commit);
 
                $self->{over}->rollback_lazy;
                $self->{over}->disconnect;

diff --git a/lib/PublicInbox/V2Writable.pm b/lib/PublicInbox/V2Writable.pm
index 3dd606eac1fab6d087d9e602badff1d7b2fe18ce..1ee19b2108e0e1783cf769310f06a32ddcff0b7b 100644 (file)
--- a/lib/PublicInbox/V2Writable.pm
+++ b/lib/PublicInbox/V2Writable.pm
@@ -238,7 +238,7 @@ sub idx_part {
 
 # idempotent
 sub idx_init {
-       my ($self) = @_;
+       my ($self, $opt) = @_;
        return if $self->{idx_parts};
        my $ibx = $self->{-inbox};
 
@@ -264,7 +264,7 @@ sub idx_init {
        my $over = $self->{over};
        $ibx->umask_prepare;
        $ibx->with_umask(sub {
-               $self->lock_acquire;
+               $self->lock_acquire unless ($opt && $opt->{-skip_lock});
                $over->create;
 
                # -compact can change partition count while -watch is idle
@@ -924,6 +924,19 @@ sub unindex {
                qw(-c gc.reflogExpire=now gc --prune=all)]);
 }
 
+sub index_ranges ($$$) {
+       my ($self, $reindex, $epoch_max) = @_;
+       return last_commits($self, $epoch_max) unless $reindex;
+
+       return [] if ref($reindex) ne 'HASH';
+
+       my $ranges = $reindex->{from}; # arrayref;
+       if (ref($ranges) ne 'ARRAY') {
+               die 'BUG: $reindex->{from} not an ARRAY';
+       }
+       $ranges;
+}
+
 # called for public-inbox-index
 sub index_sync {
        my ($self, $opts) = @_;
@@ -931,10 +944,10 @@ sub index_sync {
        my $epoch_max;
        my $latest = git_dir_latest($self, \$epoch_max);
        return unless defined $latest;
-       $self->idx_init; # acquire lock
+       $self->idx_init($opts); # acquire lock
        my $mm_tmp = $self->{mm}->tmp_clone;
        my $reindex = $opts->{reindex};
-       my $ranges = $reindex ? [] : $self->last_commits($epoch_max);
+       my $ranges = index_ranges($self, $reindex, $epoch_max);
 
        my $high = $self->{mm}->num_highwater();
        my $regen = $self->index_prepare($opts, $epoch_max, $ranges);

diff --git a/lib/PublicInbox/Xapcmd.pm b/lib/PublicInbox/Xapcmd.pm
index d2de874357ab24b1f3e90e48baa221a7c3ac6578..4555340a6d7e8b2fd0eed01a4258074c07c5a167 100644 (file)
--- a/lib/PublicInbox/Xapcmd.pm
+++ b/lib/PublicInbox/Xapcmd.pm
@@ -5,6 +5,7 @@ use strict;
 use warnings;
 use PublicInbox::Spawn qw(which spawn);
 use PublicInbox::Over;
+use PublicInbox::Search;
 use File::Temp qw(tempdir);
 use File::Path qw(remove_tree);
 
@@ -12,20 +13,33 @@ use File::Path qw(remove_tree);
 # commands with a version number suffix (e.g. "xapian-compact-1.5")
 our $XAPIAN_COMPACT = $ENV{XAPIAN_COMPACT} || 'xapian-compact';
 
-sub commit_changes ($$$) {
-       my ($im, $old, $new) = @_;
+sub commit_changes ($$$$) {
+       my ($ibx, $old, $new, $opt) = @_;
+
+       my $reindex = $opt->{reindex};
+       my $im = $ibx->importer(0);
+       $im->lock_acquire if $reindex;
+
        my @st = stat($old) or die "failed to stat($old): $!\n";
 
        my $over = "$old/over.sqlite3";
        if (-f $over) {
                $over = PublicInbox::Over->new($over);
                $over->connect->sqlite_backup_to_file("$new/over.sqlite3");
+               $over = undef;
        }
        rename($old, "$new/old") or die "rename $old => $new/old: $!\n";
        chmod($st[2] & 07777, $new) or die "chmod $old: $!\n";
        rename($new, $old) or die "rename $new => $old: $!\n";
-       $im->lock_release;
        remove_tree("$old/old") or die "failed to remove $old/old: $!\n";
+
+       if ($reindex) {
+               $opt->{-skip_lock} = 1;
+               PublicInbox::Admin::index_inbox($ibx, $opt);
+               # implicit lock_release
+       } else {
+               $im->lock_release;
+       }
 }
 
 sub xspawn {
@@ -47,6 +61,27 @@ sub runnable_or_die ($) {
        which($exe) or die "$exe not found in PATH\n";
 }
 
+sub prepare_reindex ($$) {
+       my ($ibx, $reindex) = @_;
+       if ($ibx->{version} == 1) {
+               my $dir = $ibx->search->xdir(1);
+               my $xdb = Search::Xapian::Database->new($dir);
+               if (my $lc = $xdb->get_metadata('last_commit')) {
+                       $reindex->{from} = $lc;
+               }
+       } else { # v2
+               my $v2w = $ibx->importer(0);
+               my $max;
+               $v2w->git_dir_latest(\$max) or return;
+               my $from = $reindex->{from};
+               my $mm = $ibx->mm;
+               my $v = PublicInbox::Search::SCHEMA_VERSION();
+               foreach my $i (0..$max) {
+                       $from->[$i] = $mm->last_commit_xap($v, $i);
+               }
+       }
+}
+
 sub run {
        my ($ibx, $cmd, $env, $opt) = @_;
        $opt ||= {};
@@ -54,8 +89,14 @@ sub run {
        my $exe = $cmd->[0];
        my $pfx = $exe;
        runnable_or_die($XAPIAN_COMPACT) if $opt->{compact};
+
+       my $reindex; # v1:{ from => $x40 }, v2:{ from => [ $x40, $x40, .. ] } }
+       my $from; # per-epoch ranges
+
        if (ref($exe) eq 'CODE') {
                $pfx = 'CODE';
+               $reindex = $opt->{reindex} = {};
+               $from = $reindex->{from} = [];
                require Search::Xapian::WritableDatabase;
        } else {
                runnable_or_die($exe);
@@ -64,7 +105,7 @@ sub run {
        my $old = $ibx->search->xdir(1);
        -d $old or die "$old does not exist\n";
        my $new = tempdir("$pfx-XXXXXXXX", DIR => $dir);
-       my $v = $ibx->{version} || 1;
+       my $v = $ibx->{version} ||= 1;
        my @cmds;
        if ($v == 1) {
                push @cmds, [@$cmd, $old, $new];
@@ -85,6 +126,13 @@ sub run {
        my $max = $opt->{jobs} || scalar(@cmds);
        $ibx->with_umask(sub {
                $im->lock_acquire;
+
+               # fine-grained locking if we prepare for reindex
+               if ($reindex) {
+                       prepare_reindex($ibx, $reindex);
+                       $im->lock_release;
+               }
+               delete($ibx->{$_}) for (qw(mm over search)); # cleanup
                my %pids;
                while (@cmds) {
                        while (scalar(keys(%pids)) < $max && scalar(@cmds)) {
@@ -98,7 +146,7 @@ sub run {
                                die join(' ', @$x)." failed: $?\n" if $?;
                        }
                }
-               commit_changes($im, $old, $new);
+               commit_changes($ibx, $old, $new, $opt);
        });
 }