* [PATCH 2/3] xcpdb: -R$SHARDS creates new shards with correct perms
2021-09-23 5:53 [PATCH 0/3] xcpdb-related fixes Eric Wong
2021-09-23 5:53 ` [PATCH 1/3] test_common: reset umask on non-forking run_script Eric Wong
@ 2021-09-23 5:53 ` Eric Wong
2021-09-23 5:53 ` [PATCH 3/3] xcpdb: avoid race when shards are added Eric Wong
2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2021-09-23 5:53 UTC (permalink / raw)
To: meta
"Correct" meaning the permissions match that of the parent
xap15 or ei15 directory.
---
lib/PublicInbox/Xapcmd.pm | 15 ++++++++++-----
t/extsearch.t | 7 +++++++
2 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/lib/PublicInbox/Xapcmd.pm b/lib/PublicInbox/Xapcmd.pm
index b962fa84..daef896c 100644
--- a/lib/PublicInbox/Xapcmd.pm
+++ b/lib/PublicInbox/Xapcmd.pm
@@ -22,11 +22,16 @@ sub commit_changes ($$$$) {
$SIG{INT} or die 'BUG: $SIG{INT} not handled';
my @old_shard;
my $over_chg;
+ my $mode;
while (my ($old, $newdir) = each %$tmp) {
next if $old eq ''; # no invalid paths
- my @st = stat($old);
- if (!@st && !defined($opt->{reshard})) {
+ $mode //= do {
+ my ($dname) = ($old =~ m!(.*/)[^/]+/*\z!);
+ (stat($dname))[2];
+ };
+ my $have_old = -e $old;
+ if (!$have_old && !defined($opt->{reshard})) {
die "failed to stat($old): $!";
}
@@ -46,13 +51,13 @@ sub commit_changes ($$$$) {
next;
}
- if (@st) {
- chmod($st[2] & 07777, $new) or die "chmod $old: $!\n";
+ chmod($mode & 07777, $new) or die "chmod($new): $!\n";
+ if ($have_old) {
rename($old, "$new/old") or
die "rename $old => $new/old: $!\n";
}
rename($new, $old) or die "rename $new => $old: $!\n";
- if (@st) {
+ if ($have_old) {
my $prev = "$old/old";
remove_tree($prev) or
die "failed to remove $prev: $!\n";
diff --git a/t/extsearch.t b/t/extsearch.t
index ad4f2c6d..b2b994f6 100644
--- a/t/extsearch.t
+++ b/t/extsearch.t
@@ -423,6 +423,7 @@ if ('dedupe + dry-run') {
'--dry-run alone fails');
}
+# chmod 0755, $home or xbail "chmod: $!";
for my $j (1, 3, 6) {
my $o = { 2 => \(my $err = '') };
my $d = "$home/extindex-j$j";
@@ -436,11 +437,17 @@ for my $j (1, 3, 6) {
SKIP: {
my $d = "$home/extindex-j1";
+ my @ei_dir = glob("$d/ei*/");
+ chmod 0755, $ei_dir[0] or xbail "chmod: $!";
+ my $mode = sprintf('%04o', 07777 & (stat($ei_dir[0]))[2]);
+ is($mode, '0755', 'mode set on ei*/ dir');
my $o = { 2 => \(my $err = '') };
ok(run_script([qw(-xcpdb -R4), $d]), 'xcpdb R4');
my @dirs = glob("$d/ei*/?");
for my $i (0..3) {
is(grep(m!/ei[0-9]+/$i\z!, @dirs), 1, "shard [$i] created");
+ my $m = sprintf('%04o', 07777 & (stat($dirs[$i]))[2]);
+ is($m, $mode, "shard [$i] mode");
}
for my $i (4..5) {
is(grep(m!/ei[0-9]+/$i\z!, @dirs), 0, "no shard [$i]");
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 3/3] xcpdb: avoid race when shards are added
2021-09-23 5:53 [PATCH 0/3] xcpdb-related fixes Eric Wong
2021-09-23 5:53 ` [PATCH 1/3] test_common: reset umask on non-forking run_script Eric Wong
2021-09-23 5:53 ` [PATCH 2/3] xcpdb: -R$SHARDS creates new shards with correct perms Eric Wong
@ 2021-09-23 5:53 ` Eric Wong
2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2021-09-23 5:53 UTC (permalink / raw)
To: meta
It's possible for the rename() sequence to cause read-only
daemons using ->xdb_shards_flat to load an incomplete set of
contiguous shards and get invalid docids for search results.
With this change, we favor the case where search is momentarily
unavailable rather than giving wrong results during the small
window where Xapcmd->commit_changes runs.
---
lib/PublicInbox/Xapcmd.pm | 31 +++++++++++++++++--------------
1 file changed, 17 insertions(+), 14 deletions(-)
diff --git a/lib/PublicInbox/Xapcmd.pm b/lib/PublicInbox/Xapcmd.pm
index daef896c..44e0f8e5 100644
--- a/lib/PublicInbox/Xapcmd.pm
+++ b/lib/PublicInbox/Xapcmd.pm
@@ -20,16 +20,23 @@ sub commit_changes ($$$$) {
my $reshard = $opt->{reshard};
$SIG{INT} or die 'BUG: $SIG{INT} not handled';
- my @old_shard;
- my $over_chg;
- my $mode;
-
- while (my ($old, $newdir) = each %$tmp) {
+ my (@old_shard, $over_chg);
+
+ # Sort shards highest-to-lowest, since ->xdb_shards_flat
+ # determines the number of shards to load based on the max;
+ # and we'd rather xdb_shards_flat to momentarily fail rather
+ # than load out-of-date shards
+ my @order = sort {
+ my ($x) = ($a =~ m!/([0-9]+)/*\z!);
+ my ($y) = ($b =~ m!/([0-9]+)/*\z!);
+ ($y // -1) <=> ($x // -1) # we may have non-shards
+ } keys %$tmp;
+
+ my ($dname) = ($order[0] =~ m!(.*/)[^/]+/*\z!);
+ my $mode = (stat($dname))[2];
+ for my $old (@order) {
next if $old eq ''; # no invalid paths
- $mode //= do {
- my ($dname) = ($old =~ m!(.*/)[^/]+/*\z!);
- (stat($dname))[2];
- };
+ my $newdir = $tmp->{$old};
my $have_old = -e $old;
if (!$have_old && !defined($opt->{reshard})) {
die "failed to stat($old): $!";
@@ -57,11 +64,7 @@ sub commit_changes ($$$$) {
die "rename $old => $new/old: $!\n";
}
rename($new, $old) or die "rename $new => $old: $!\n";
- if ($have_old) {
- my $prev = "$old/old";
- remove_tree($prev) or
- die "failed to remove $prev: $!\n";
- }
+ push @old_shard, "$old/old" if $have_old;
}
# trigger ->check_inodes in read-only daemons
^ permalink raw reply related [flat|nested] 4+ messages in thread