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-rw-r--r--doc/src/sgml/protocol.sgml13
-rw-r--r--doc/src/sgml/ref/pg_basebackup.sgml16
-rw-r--r--src/backend/replication/basebackup.c227
-rw-r--r--src/backend/replication/repl_gram.y8
-rw-r--r--src/backend/replication/repl_scanner.l1
-rw-r--r--src/bin/pg_basebackup/pg_basebackup.c38
-rw-r--r--src/bin/pg_basebackup/t/010_pg_basebackup.pl62
7 files changed, 352 insertions, 13 deletions
diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index 8c488506fad..b94dd4ac654 100644
--- a/doc/src/sgml/protocol.sgml
+++ b/doc/src/sgml/protocol.sgml
@@ -2382,7 +2382,7 @@ The commands accepted in replication mode are:
</varlistentry>
<varlistentry>
- <term><literal>BASE_BACKUP</literal> [ <literal>LABEL</literal> <replaceable>'label'</replaceable> ] [ <literal>PROGRESS</literal> ] [ <literal>FAST</literal> ] [ <literal>WAL</literal> ] [ <literal>NOWAIT</literal> ] [ <literal>MAX_RATE</literal> <replaceable>rate</replaceable> ] [ <literal>TABLESPACE_MAP</literal> ]
+ <term><literal>BASE_BACKUP</literal> [ <literal>LABEL</literal> <replaceable>'label'</replaceable> ] [ <literal>PROGRESS</literal> ] [ <literal>FAST</literal> ] [ <literal>WAL</literal> ] [ <literal>NOWAIT</literal> ] [ <literal>MAX_RATE</literal> <replaceable>rate</replaceable> ] [ <literal>TABLESPACE_MAP</literal> ] [ <literal>NOVERIFY_CHECKSUMS</literal> ]
<indexterm><primary>BASE_BACKUP</primary></indexterm>
</term>
<listitem>
@@ -2481,6 +2481,17 @@ The commands accepted in replication mode are:
</para>
</listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><literal>NOVERIFY_CHECKSUMS</literal></term>
+ <listitem>
+ <para>
+ By default, checksums are verified during a base backup if they are
+ enabled. Specifying <literal>NOVERIFY_CHECKSUMS</literal> disables
+ this verification.
+ </para>
+ </listitem>
+ </varlistentry>
</variablelist>
</para>
<para>
diff --git a/doc/src/sgml/ref/pg_basebackup.sgml b/doc/src/sgml/ref/pg_basebackup.sgml
index e8921b1bb48..95045669c93 100644
--- a/doc/src/sgml/ref/pg_basebackup.sgml
+++ b/doc/src/sgml/ref/pg_basebackup.sgml
@@ -507,6 +507,22 @@ PostgreSQL documentation
</varlistentry>
<varlistentry>
+ <term><option>-k</option></term>
+ <term><option>--no-verify-checksums</option></term>
+ <listitem>
+ <para>
+ Disables verification of checksums, if they are enabled on the server
+ the base backup is taken from.
+ </para>
+ <para>
+ By default, checksums are verified and checksum failures will result in
+ a non-zero exit status. However, the base backup will not be removed in
+ this case, as if the <literal>--no-clean</literal> option was used.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><option>-v</option></term>
<term><option>--verbose</option></term>
<listitem>
diff --git a/src/backend/replication/basebackup.c b/src/backend/replication/basebackup.c
index 516eea57f8d..300dbfbcd6a 100644
--- a/src/backend/replication/basebackup.c
+++ b/src/backend/replication/basebackup.c
@@ -31,6 +31,8 @@
#include "replication/basebackup.h"
#include "replication/walsender.h"
#include "replication/walsender_private.h"
+#include "storage/bufpage.h"
+#include "storage/checksum.h"
#include "storage/dsm_impl.h"
#include "storage/fd.h"
#include "storage/ipc.h"
@@ -70,6 +72,7 @@ static void parse_basebackup_options(List *options, basebackup_options *opt);
static void SendXlogRecPtrResult(XLogRecPtr ptr, TimeLineID tli);
static int compareWalFileNames(const void *a, const void *b);
static void throttle(size_t increment);
+static bool is_checksummed_file(const char *fullpath, const char *filename);
/* Was the backup currently in-progress initiated in recovery mode? */
static bool backup_started_in_recovery = false;
@@ -99,6 +102,15 @@ static TimeOffset elapsed_min_unit;
/* The last check of the transfer rate. */
static TimestampTz throttled_last;
+/* The starting XLOG position of the base backup. */
+static XLogRecPtr startptr;
+
+/* Total number of checksum failures during base backup. */
+static int64 total_checksum_failures;
+
+/* Do not verify checksums. */
+static bool noverify_checksums = false;
+
/*
* The contents of these directories are removed or recreated during server
* start so they are not included in backups. The directories themselves are
@@ -176,6 +188,18 @@ static const char *excludeFiles[] =
};
/*
+ * List of files excluded from checksum validation.
+ */
+static const char *noChecksumFiles[] = {
+ "pg_control",
+ "pg_filenode.map",
+ "pg_internal.init",
+ "PG_VERSION",
+ NULL,
+};
+
+
+/*
* Called when ERROR or FATAL happens in perform_base_backup() after
* we have started the backup - make sure we end it!
*/
@@ -194,7 +218,6 @@ base_backup_cleanup(int code, Datum arg)
static void
perform_base_backup(basebackup_options *opt)
{
- XLogRecPtr startptr;
TimeLineID starttli;
XLogRecPtr endptr;
TimeLineID endtli;
@@ -210,6 +233,8 @@ perform_base_backup(basebackup_options *opt)
labelfile = makeStringInfo();
tblspc_map_file = makeStringInfo();
+ total_checksum_failures = 0;
+
startptr = do_pg_start_backup(opt->label, opt->fastcheckpoint, &starttli,
labelfile, &tablespaces,
tblspc_map_file,
@@ -568,6 +593,17 @@ perform_base_backup(basebackup_options *opt)
pq_putemptymessage('c');
}
SendXlogRecPtrResult(endptr, endtli);
+
+ if (total_checksum_failures)
+ {
+ if (total_checksum_failures > 1)
+ ereport(WARNING,
+ (errmsg("%ld total checksum verification failures", total_checksum_failures)));
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_CORRUPTED),
+ errmsg("checksum verification failure during base backup")));
+ }
+
}
/*
@@ -597,6 +633,7 @@ parse_basebackup_options(List *options, basebackup_options *opt)
bool o_wal = false;
bool o_maxrate = false;
bool o_tablespace_map = false;
+ bool o_noverify_checksums = false;
MemSet(opt, 0, sizeof(*opt));
foreach(lopt, options)
@@ -676,6 +713,15 @@ parse_basebackup_options(List *options, basebackup_options *opt)
opt->sendtblspcmapfile = true;
o_tablespace_map = true;
}
+ else if (strcmp(defel->defname, "noverify_checksums") == 0)
+ {
+ if (o_noverify_checksums)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("duplicate option \"%s\"", defel->defname)));
+ noverify_checksums = true;
+ o_noverify_checksums = true;
+ }
else
elog(ERROR, "option \"%s\" not recognized",
defel->defname);
@@ -1257,6 +1303,33 @@ sendDir(const char *path, int basepathlen, bool sizeonly, List *tablespaces,
return size;
}
+/*
+ * Check if a file should have its checksum validated.
+ * We validate checksums on files in regular tablespaces
+ * (including global and default) only, and in those there
+ * are some files that are explicitly excluded.
+ */
+static bool
+is_checksummed_file(const char *fullpath, const char *filename)
+{
+ const char **f;
+
+ /* Check that the file is in a tablespace */
+ if (strncmp(fullpath, "./global/", 9) == 0 ||
+ strncmp(fullpath, "./base/", 7) == 0 ||
+ strncmp(fullpath, "/", 1) == 0)
+ {
+ /* Compare file against noChecksumFiles skiplist */
+ for (f = noChecksumFiles; *f; f++)
+ if (strcmp(*f, filename) == 0)
+ return false;
+
+ return true;
+ }
+ else
+ return false;
+}
+
/*****
* Functions for handling tar file format
*
@@ -1277,10 +1350,20 @@ sendFile(const char *readfilename, const char *tarfilename, struct stat *statbuf
bool missing_ok)
{
FILE *fp;
+ BlockNumber blkno = 0;
+ bool block_retry = false;
char buf[TAR_SEND_SIZE];
+ uint16 checksum;
+ int checksum_failures = 0;
size_t cnt;
+ int i;
pgoff_t len = 0;
+ char *page;
size_t pad;
+ PageHeader phdr;
+ int segmentno = 0;
+ char *segmentpath;
+ bool verify_checksum = false;
fp = AllocateFile(readfilename, "rb");
if (fp == NULL)
@@ -1294,8 +1377,142 @@ sendFile(const char *readfilename, const char *tarfilename, struct stat *statbuf
_tarWriteHeader(tarfilename, NULL, statbuf, false);
+ if (!noverify_checksums && DataChecksumsEnabled())
+ {
+ char *filename;
+
+ /*
+ * Get the filename (excluding path). As last_dir_separator()
+ * includes the last directory separator, we chop that off by
+ * incrementing the pointer.
+ */
+ filename = last_dir_separator(readfilename) + 1;
+
+ if (is_checksummed_file(readfilename, filename))
+ {
+ verify_checksum = true;
+
+ /*
+ * Cut off at the segment boundary (".") to get the segment number
+ * in order to mix it into the checksum.
+ */
+ segmentpath = strstr(filename, ".");
+ if (segmentpath != NULL)
+ {
+ segmentno = atoi(segmentpath + 1);
+ if (segmentno == 0)
+ ereport(ERROR,
+ (errmsg("invalid segment number %d in file \"%s\"",
+ segmentno, filename)));
+ }
+ }
+ }
+
while ((cnt = fread(buf, 1, Min(sizeof(buf), statbuf->st_size - len), fp)) > 0)
{
+ if (verify_checksum)
+ {
+ /*
+ * The checksums are verified at block level, so we iterate over
+ * the buffer in chunks of BLCKSZ, after making sure that
+ * TAR_SEND_SIZE/buf is divisible by BLCKSZ and we read a multiple
+ * of BLCKSZ bytes.
+ */
+ Assert(TAR_SEND_SIZE % BLCKSZ == 0);
+
+ if (cnt % BLCKSZ != 0)
+ {
+ ereport(WARNING,
+ (errmsg("cannot verify checksum in file \"%s\", block "
+ "%d: read buffer size %d and page size %d "
+ "differ",
+ readfilename, blkno, (int) cnt, BLCKSZ)));
+ verify_checksum = false;
+ continue;
+ }
+ for (i = 0; i < cnt / BLCKSZ; i++)
+ {
+ page = buf + BLCKSZ * i;
+
+ /*
+ * Only check pages which have not been modified since the
+ * start of the base backup. Otherwise, they might have been
+ * written only halfway and the checksum would not be valid.
+ * However, replaying WAL would reinstate the correct page in
+ * this case.
+ */
+ if (PageGetLSN(page) < startptr)
+ {
+ checksum = pg_checksum_page((char *) page, blkno + segmentno * RELSEG_SIZE);
+ phdr = (PageHeader) page;
+ if (phdr->pd_checksum != checksum)
+ {
+ /*
+ * Retry the block on the first failure. It's
+ * possible that we read the first 4K page of the
+ * block just before postgres updated the entire block
+ * so it ends up looking torn to us. We only need to
+ * retry once because the LSN should be updated to
+ * something we can ignore on the next pass. If the
+ * error happens again then it is a true validation
+ * failure.
+ */
+ if (block_retry == false)
+ {
+ /* Reread the failed block */
+ if (fseek(fp, -(cnt - BLCKSZ * i), SEEK_CUR) == -1)
+ {
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not fseek in file \"%s\": %m",
+ readfilename)));
+ }
+
+ if (fread(buf + BLCKSZ * i, 1, BLCKSZ, fp) != BLCKSZ)
+ {
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not reread block %d of file \"%s\": %m",
+ blkno, readfilename)));
+ }
+
+ if (fseek(fp, cnt - BLCKSZ * i - BLCKSZ, SEEK_CUR) == -1)
+ {
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not fseek in file \"%s\": %m",
+ readfilename)));
+ }
+
+ /* Set flag so we know a retry was attempted */
+ block_retry = true;
+
+ /* Reset loop to validate the block again */
+ i--;
+ continue;
+ }
+
+ checksum_failures++;
+
+ if (checksum_failures <= 5)
+ ereport(WARNING,
+ (errmsg("checksum verification failed in "
+ "file \"%s\", block %d: calculated "
+ "%X but expected %X",
+ readfilename, blkno, checksum,
+ phdr->pd_checksum)));
+ if (checksum_failures == 5)
+ ereport(WARNING,
+ (errmsg("further checksum verification "
+ "failures in file \"%s\" will not "
+ "be reported", readfilename)));
+ }
+ }
+ block_retry = false;
+ blkno++;
+ }
+ }
+
/* Send the chunk as a CopyData message */
if (pq_putmessage('d', buf, cnt))
ereport(ERROR,
@@ -1341,6 +1558,14 @@ sendFile(const char *readfilename, const char *tarfilename, struct stat *statbuf
FreeFile(fp);
+ if (checksum_failures > 1)
+ {
+ ereport(WARNING,
+ (errmsg("file \"%s\" has a total of %d checksum verification "
+ "failures", readfilename, checksum_failures)));
+ }
+ total_checksum_failures += checksum_failures;
+
return true;
}
diff --git a/src/backend/replication/repl_gram.y b/src/backend/replication/repl_gram.y
index beb2c2877b2..843a878ff37 100644
--- a/src/backend/replication/repl_gram.y
+++ b/src/backend/replication/repl_gram.y
@@ -77,6 +77,7 @@ static SQLCmd *make_sqlcmd(void);
%token K_MAX_RATE
%token K_WAL
%token K_TABLESPACE_MAP
+%token K_NOVERIFY_CHECKSUMS
%token K_TIMELINE
%token K_PHYSICAL
%token K_LOGICAL
@@ -154,7 +155,7 @@ var_name: IDENT { $$ = $1; }
/*
* BASE_BACKUP [LABEL '<label>'] [PROGRESS] [FAST] [WAL] [NOWAIT]
- * [MAX_RATE %d] [TABLESPACE_MAP]
+ * [MAX_RATE %d] [TABLESPACE_MAP] [NOVERIFY_CHECKSUMS]
*/
base_backup:
K_BASE_BACKUP base_backup_opt_list
@@ -208,6 +209,11 @@ base_backup_opt:
$$ = makeDefElem("tablespace_map",
(Node *)makeInteger(true), -1);
}
+ | K_NOVERIFY_CHECKSUMS
+ {
+ $$ = makeDefElem("noverify_checksums",
+ (Node *)makeInteger(true), -1);
+ }
;
create_replication_slot:
diff --git a/src/backend/replication/repl_scanner.l b/src/backend/replication/repl_scanner.l
index fb48241e482..7bb501f5949 100644
--- a/src/backend/replication/repl_scanner.l
+++ b/src/backend/replication/repl_scanner.l
@@ -92,6 +92,7 @@ PROGRESS { return K_PROGRESS; }
MAX_RATE { return K_MAX_RATE; }
WAL { return K_WAL; }
TABLESPACE_MAP { return K_TABLESPACE_MAP; }
+NOVERIFY_CHECKSUMS { return K_NOVERIFY_CHECKSUMS; }
TIMELINE { return K_TIMELINE; }
START_REPLICATION { return K_START_REPLICATION; }
CREATE_REPLICATION_SLOT { return K_CREATE_REPLICATION_SLOT; }
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 1b325920635..8610fe8a1a8 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -39,6 +39,7 @@
#include "replication/basebackup.h"
#include "streamutil.h"
+#define ERRCODE_DATA_CORRUPTED "XX001"
typedef struct TablespaceListCell
{
@@ -81,6 +82,7 @@ static char *xlog_dir = NULL;
static char format = 'p'; /* p(lain)/t(ar) */
static char *label = "pg_basebackup base backup";
static bool noclean = false;
+static bool checksum_failure = false;
static bool showprogress = false;
static int verbose = 0;
static int compresslevel = 0;
@@ -95,6 +97,7 @@ static char *replication_slot = NULL;
static bool temp_replication_slot = true;
static bool create_slot = false;
static bool no_slot = false;
+static bool verify_checksums = true;
static bool success = false;
static bool made_new_pgdata = false;
@@ -155,7 +158,7 @@ cleanup_directories_atexit(void)
if (success || in_log_streamer)
return;
- if (!noclean)
+ if (!noclean && !checksum_failure)
{
if (made_new_pgdata)
{
@@ -195,7 +198,7 @@ cleanup_directories_atexit(void)
}
else
{
- if (made_new_pgdata || found_existing_pgdata)
+ if ((made_new_pgdata || found_existing_pgdata) && !checksum_failure)
fprintf(stderr,
_("%s: data directory \"%s\" not removed at user's request\n"),
progname, basedir);
@@ -206,7 +209,7 @@ cleanup_directories_atexit(void)
progname, xlog_dir);
}
- if (made_tablespace_dirs || found_tablespace_dirs)
+ if ((made_tablespace_dirs || found_tablespace_dirs) && !checksum_failure)
fprintf(stderr,
_("%s: changes to tablespace directories will not be undone\n"),
progname);
@@ -360,6 +363,8 @@ usage(void)
printf(_(" -P, --progress show progress information\n"));
printf(_(" -S, --slot=SLOTNAME replication slot to use\n"));
printf(_(" --no-slot prevent creation of temporary replication slot\n"));
+ printf(_(" -k, --no-verify-checksums\n"
+ " do not verify checksums\n"));
printf(_(" -v, --verbose output verbose messages\n"));
printf(_(" -V, --version output version information, then exit\n"));
printf(_(" -?, --help show this help, then exit\n"));
@@ -1808,14 +1813,15 @@ BaseBackup(void)
}
basebkp =
- psprintf("BASE_BACKUP LABEL '%s' %s %s %s %s %s %s",
+ psprintf("BASE_BACKUP LABEL '%s' %s %s %s %s %s %s %s",
escaped_label,
showprogress ? "PROGRESS" : "",
includewal == FETCH_WAL ? "WAL" : "",
fastcheckpoint ? "FAST" : "",
includewal == NO_WAL ? "" : "NOWAIT",
maxrate_clause ? maxrate_clause : "",
- format == 't' ? "TABLESPACE_MAP" : "");
+ format == 't' ? "TABLESPACE_MAP" : "",
+ verify_checksums ? "" : "NOVERIFY_CHECKSUMS");
if (PQsendQuery(conn, basebkp) == 0)
{
@@ -1970,8 +1976,20 @@ BaseBackup(void)
res = PQgetResult(conn);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
- fprintf(stderr, _("%s: final receive failed: %s"),
- progname, PQerrorMessage(conn));
+ const char *sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
+
+ if (sqlstate &&
+ strcmp(sqlstate, ERRCODE_DATA_CORRUPTED) == 0)
+ {
+ fprintf(stderr, _("%s: checksum error occured\n"),
+ progname);
+ checksum_failure = true;
+ }
+ else
+ {
+ fprintf(stderr, _("%s: final receive failed: %s"),
+ progname, PQerrorMessage(conn));
+ }
disconnect_and_exit(1);
}
@@ -2140,6 +2158,7 @@ main(int argc, char **argv)
{"progress", no_argument, NULL, 'P'},
{"waldir", required_argument, NULL, 1},
{"no-slot", no_argument, NULL, 2},
+ {"no-verify-checksums", no_argument, NULL, 'k'},
{NULL, 0, NULL, 0}
};
int c;
@@ -2166,7 +2185,7 @@ main(int argc, char **argv)
atexit(cleanup_directories_atexit);
- while ((c = getopt_long(argc, argv, "CD:F:r:RS:T:X:l:nNzZ:d:c:h:p:U:s:wWvP",
+ while ((c = getopt_long(argc, argv, "CD:F:r:RS:T:X:l:nNzZ:d:c:h:p:U:s:wWkvP",
long_options, &option_index)) != -1)
{
switch (c)
@@ -2308,6 +2327,9 @@ main(int argc, char **argv)
case 'P':
showprogress = true;
break;
+ case 'k':
+ verify_checksums = false;
+ break;
default:
/*
diff --git a/src/bin/pg_basebackup/t/010_pg_basebackup.pl b/src/bin/pg_basebackup/t/010_pg_basebackup.pl
index 32d21ce6442..3162cdcd01b 100644
--- a/src/bin/pg_basebackup/t/010_pg_basebackup.pl
+++ b/src/bin/pg_basebackup/t/010_pg_basebackup.pl
@@ -5,7 +5,7 @@ use Config;
use File::Basename qw(basename dirname);
use PostgresNode;
use TestLib;
-use Test::More tests => 93;
+use Test::More tests => 104;
program_help_ok('pg_basebackup');
program_version_ok('pg_basebackup');
@@ -16,7 +16,7 @@ my $tempdir = TestLib::tempdir;
my $node = get_new_node('main');
# Initialize node without replication settings
-$node->init;
+$node->init(extra => [ '--data-checksums' ]);
$node->start;
my $pgdata = $node->data_dir;
@@ -402,3 +402,61 @@ like(
slurp_file("$tempdir/backupxs_sl_R/recovery.conf"),
qr/^primary_slot_name = 'slot1'\n/m,
'recovery.conf sets primary_slot_name');
+
+my $checksum = $node->safe_psql('postgres', 'SHOW data_checksums;');
+is($checksum, 'on', 'checksums are enabled');
+
+# get relfilenodes of relations to corrupt
+my $pg_class = $node->safe_psql('postgres',
+ q{SELECT pg_relation_filepath('pg_class')}
+);
+my $pg_index = $node->safe_psql('postgres',
+ q{SELECT pg_relation_filepath('pg_index')}
+);
+
+# induce corruption
+open $file, '+<', "$pgdata/$pg_class";
+seek($file, 4000, 0);
+syswrite($file, '\0\0\0\0\0\0\0\0\0');
+close $file;
+
+$node->command_checks_all([ 'pg_basebackup', '-D', "$tempdir/backup_corrupt"],
+ 1,
+ [qr{^$}],
+ [qr/^WARNING.*checksum verification failed/s],
+ 'pg_basebackup reports checksum mismatch'
+);
+
+# induce further corruption in 5 more blocks
+open $file, '+<', "$pgdata/$pg_class";
+my @offsets = (12192, 20384, 28576, 36768, 44960);
+foreach my $offset (@offsets) {
+ seek($file, $offset, 0);
+ syswrite($file, '\0\0\0\0\0\0\0\0\0');
+}
+close $file;
+
+$node->command_checks_all([ 'pg_basebackup', '-D', "$tempdir/backup_corrupt2"],
+ 1,
+ [qr{^$}],
+ [qr/^WARNING.*further.*failures.*will.not.be.reported/s],
+ 'pg_basebackup does not report more than 5 checksum mismatches'
+);
+
+# induce corruption in a second file
+open $file, '+<', "$pgdata/$pg_index";
+seek($file, 4000, 0);
+syswrite($file, '\0\0\0\0\0\0\0\0\0');
+close $file;
+
+$node->command_checks_all([ 'pg_basebackup', '-D', "$tempdir/backup_corrupt3"],
+ 1,
+ [qr{^$}],
+ [qr/^WARNING.*7 total checksum verification failures/s],
+ 'pg_basebackup correctly report the total number of checksum mismatches'
+);
+
+# do not verify checksums, should return ok
+$node->command_ok(
+ [ 'pg_basebackup', '-D', "$tempdir/backup_corrupt4", '-k' ],
+ 'pg_basebackup with -k does not report checksum mismatch');
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-01 07:11:32 +0000