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Peter Dillinger fc9d4071f0 Fast path for detecting unchanged prefix_extractor (#9407) 
Summary:
Fixes a major performance regression in 6.26, where
extra CPU is spent in SliceTransform::AsString when reads involve
a prefix_extractor (Get, MultiGet, Seek). Common case performance
is now better than 6.25.

This change creates a "fast path" for verifying that the current prefix
extractor is unchanged and compatible with what was used to
generate a table file. This fast path detects the common case by
pointer comparison on the current prefix_extractor and a "known
good" prefix extractor (if applicable) that is saved at the time the
table reader is opened. The "known good" prefix extractor is saved
as another shared_ptr copy (in an existing field, however) to ensure
the pointer is not recycled.

When the prefix_extractor has changed to a different instance but
same compatible configuration (rare, odd), performance is still a
regression compared to 6.25, but this is likely acceptable because
of the oddity of such a case. The performance of incompatible
prefix_extractor is essentially unchanged.

Also fixed a minor case (ForwardIterator) where a prefix_extractor
could be used via a raw pointer after being freed as a shared_ptr,
if replaced via SetOptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9407

Test Plan:
## Performance
Populate DB with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12`

Running head-to-head comparisons simultaneously with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -use_existing_db -readonly -benchmarks=seekrandom -num=10000000 -duration=20 -disable_wal=1 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12`

Below each is compared by ops/sec vs. baseline which is version 6.25 (multiple baseline runs because of variable machine load)

v6.26: 4833 vs. 6698 (<- major regression!)
v6.27: 4737 vs. 6397 (still)
New: 6704 vs. 6461 (better than baseline in common case)
Disabled fastpath: 4843 vs. 6389 (e.g. if prefix extractor instance changes but is still compatible)
Changed prefix size (no usable filter) in new: 787 vs. 5927
Changed prefix size (no usable filter) in new & baseline: 773 vs. 784

Reviewed By: mrambacher

Differential Revision: D33677812

Pulled By: pdillinger

fbshipit-source-id: 571d9711c461fb97f957378a061b7e7dbc4d6a76
2022-01-21 11:37:46 -08:00
..
blob Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
compaction Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
db_impl Fix flaky EventListenerTest.DisableBGCompaction (#9400) 2022-01-21 08:25:09 -08:00
arena_wrapped_db_iter.cc Rename ImmutableOptions variables (#8409) 2021-06-16 16:51:38 -07:00
arena_wrapped_db_iter.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
builder.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
builder.h Expose blob file information through the EventListener interface (#8675) 2021-09-16 17:23:36 -07:00
c_test.c Fix a bug in C-binding causing iterator to return incorrect result (#9343) 2021-12-30 12:48:07 -08:00
c.cc Take compression level_values as const pointer (#9376) 2022-01-12 08:34:53 -08:00
column_family_test.cc More refactoring ahead of footer & meta changes (#9240) 2021-12-10 08:13:26 -08:00
column_family.cc Fix bug affecting GetSortedWalFiles, Backups, Checkpoint (#9208) 2021-11-24 14:52:00 -08:00
column_family.h Add DB properties for BlobDB (#8734) 2021-09-08 12:22:04 -07:00
compact_files_test.cc Compaction should not move data to up level (#8116) 2021-03-29 17:10:42 -07:00
comparator_db_test.cc More refactoring ahead of footer & meta changes (#9240) 2021-12-10 08:13:26 -08:00
convenience.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
corruption_test.cc Make the Env class Customizable (#9293) 2022-01-04 16:45:49 -08:00
cuckoo_table_db_test.cc Experimental support for SST unique IDs (#8990) 2021-10-18 23:32:01 -07:00
db_basic_test.cc Fix clang13 build error (#9374) 2022-01-11 10:36:22 -08:00
db_block_cache_test.cc New stable, fixed-length cache keys (#9126) 2021-12-16 17:15:13 -08:00
db_bloom_filter_test.cc More refactoring ahead of footer & meta changes (#9240) 2021-12-10 08:13:26 -08:00
db_compaction_filter_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_compaction_test.cc Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
db_dynamic_level_test.cc Make SystemClock into a Customizable Class (#8636) 2021-09-21 09:23:48 -07:00
db_encryption_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_filesnapshot.cc Fix bug affecting GetSortedWalFiles, Backups, Checkpoint (#9208) 2021-11-24 14:52:00 -08:00
db_flush_test.cc Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
db_info_dumper.cc Allow WAL dir to change with db dir (#8582) 2021-07-30 12:16:44 -07:00
db_info_dumper.h Add a DB Session ID (#6959) 2020-06-15 10:47:02 -07:00
db_inplace_update_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_io_failure_test.cc Enable a few unit tests to use custom Env objects (#9087) 2021-11-08 11:05:59 -08:00
db_iter_stress_test.cc Make ImmutableOptions struct that inherits from ImmutableCFOptions and ImmutableDBOptions (#8262) 2021-05-05 14:00:17 -07:00
db_iter_test.cc Remove some unneeded code (#8736) 2021-09-01 14:28:58 -07:00
db_iter.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
db_iter.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
db_iterator_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_kv_checksum_test.cc Allow WriteBatch to have keys with different timestamp sizes (#8725) 2021-09-12 15:34:26 -07:00
db_log_iter_test.cc Attempt to deflake DBTestXactLogIterator.TransactionLogIteratorCorruptedLog (#8627) 2021-08-10 11:10:07 -07:00
db_logical_block_size_cache_test.cc Add further tests to ASSERT_STATUS_CHECKED (2) (#7698) 2020-12-09 21:21:16 -08:00
db_memtable_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_merge_operand_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_merge_operator_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_options_test.cc Fix an issue with MemTableRepFactory::CreateFromString (#9273) 2021-12-09 12:36:18 -08:00
db_properties_test.cc Add support for building on s390x platform (#8962) 2021-10-22 10:13:15 -07:00
db_range_del_test.cc Incremental Space Amp Compactions in Universal Style (#8655) 2021-10-20 10:04:13 -07:00
db_secondary_test.cc Make the Env class Customizable (#9293) 2022-01-04 16:45:49 -08:00
db_sst_test.cc Make the Env class Customizable (#9293) 2022-01-04 16:45:49 -08:00
db_statistics_test.cc Bytes read stat for VerifyChecksum() and VerifyFileChecksums() APIs (#8741) 2021-09-07 13:28:29 -07:00
db_table_properties_test.cc Fix backward compatibility with 2.5 through 2.7 (#9189) 2021-11-19 17:31:01 -08:00
db_tailing_iter_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
db_test_util.cc Add Options::DisableExtraChecks, clarify force_consistency_checks (#9363) 2022-01-18 17:31:03 -08:00
db_test_util.h Make the Env class Customizable (#9293) 2022-01-04 16:45:49 -08:00
db_test.cc Enable db_test running in Centos 32 bit OS and Alpine 32 bit OS (#9294) 2022-01-14 11:58:18 -08:00
db_test2.cc Fix clang13 build error (#9374) 2022-01-11 10:36:22 -08:00
db_universal_compaction_test.cc Adhere to per-DB concurrency limit when bottom-pri compactions exist (#9179) 2021-11-18 17:31:50 -08:00
db_wal_test.cc Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
db_with_timestamp_basic_test.cc Make IncreaseFullHistoryTsLow to a public API (#9221) 2021-12-23 11:03:51 -08:00
db_with_timestamp_compaction_test.cc Make MemTableRepFactory into a Customizable class (#8419) 2021-09-08 07:46:44 -07:00
db_write_buffer_manager_test.cc Enable a few unit tests to use custom Env objects (#9087) 2021-11-08 11:05:59 -08:00
db_write_test.cc Enable a few unit tests to use custom Env objects (#9087) 2021-11-08 11:05:59 -08:00
dbformat_test.cc Enable a few unit tests to use custom Env objects (#9087) 2021-11-08 11:05:59 -08:00
dbformat.cc Track per-SST user-defined timestamp information in MANIFEST (#9092) 2021-11-10 10:49:04 -08:00
dbformat.h Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
deletefile_test.cc Enable a few unit tests to use custom Env objects (#9087) 2021-11-08 11:05:59 -08:00
error_handler_fs_test.cc Fix race condition in error_handler_fs_test (#9325) 2021-12-20 23:16:52 -08:00
error_handler.cc Add a listener callback for end of auto error recovery (#9244) 2021-12-08 14:30:57 -08:00
error_handler.h cleanup error_handler related code (#9098) 2021-11-08 15:49:17 -08:00
event_helpers.cc Add a listener callback for end of auto error recovery (#9244) 2021-12-08 14:30:57 -08:00
event_helpers.h Add a listener callback for end of auto error recovery (#9244) 2021-12-08 14:30:57 -08:00
experimental.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
external_sst_file_basic_test.cc Enable a few unit tests to use custom Env objects (#9087) 2021-11-08 11:05:59 -08:00
external_sst_file_ingestion_job.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
external_sst_file_ingestion_job.h New stable, fixed-length cache keys (#9126) 2021-12-16 17:15:13 -08:00
external_sst_file_test.cc Make the Env class Customizable (#9293) 2022-01-04 16:45:49 -08:00
fault_injection_test.cc Fix a bug causing duplicate trailing entries in WritableFile (buffered IO) (#9236) 2021-12-13 09:00:36 -08:00
file_indexer_test.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
file_indexer.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
file_indexer.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
filename_test.cc Remove unused includes (#7604) 2020-10-28 23:22:27 -07:00
flush_job_test.cc Fix NotifyOnFlushCompleted() for atomic flush (#8585) 2021-08-03 13:31:10 -07:00
flush_job.cc File temperature information should be preserved when restart the DB (#9242) 2021-12-03 14:43:14 -08:00
flush_job.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
flush_scheduler.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
flush_scheduler.h Include C++ standard library headers instead of C compatibility headers (#8068) 2021-03-19 12:09:47 -07:00
forward_iterator_bench.cc Remove using namespace (#9369) 2022-01-12 09:31:12 -08:00
forward_iterator.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
forward_iterator.h Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
import_column_family_job.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
import_column_family_job.h New stable, fixed-length cache keys (#9126) 2021-12-16 17:15:13 -08:00
import_column_family_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
internal_stats.cc InternalStats::DumpCFMapStat: fix sum.w_amp (#9065) 2021-10-31 23:11:43 -07:00
internal_stats.h Support GetMapProperty() with "rocksdb.dbstats" (#9057) 2021-10-20 13:17:00 -07:00
job_context.h Fix and detect headers with missing dependencies (#8893) 2021-09-10 10:00:26 -07:00
kv_checksum.h fix compile errors in db/kv_checksum.h (#9173) 2021-11-16 10:20:50 -08:00
listener_test.cc Fix flaky EventListenerTest.DisableBGCompaction (#9400) 2022-01-21 08:25:09 -08:00
log_format.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
log_reader.cc Fix kPointInTimeRecovery handling of truncated WAL (#7701) 2020-11-30 18:11:38 -08:00
log_reader.h Real fix for race in backup custom checksum checking (#7309) 2020-08-26 10:39:20 -07:00
log_test.cc Make StringEnv, StringSink, StringSource use FS classes (#7786) 2021-01-04 16:01:01 -08:00
log_writer.cc Using existing crc32c checksum in checksum handoff for Manifest and WAL (#8412) 2021-06-25 00:47:17 -07:00
log_writer.h Include C++ standard library headers instead of C compatibility headers (#8068) 2021-03-19 12:09:47 -07:00
logs_with_prep_tracker.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
logs_with_prep_tracker.h Include C++ standard library headers instead of C compatibility headers (#8068) 2021-03-19 12:09:47 -07:00
lookup_key.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
malloc_stats.cc Replace most typedef with using= (#8751) 2021-09-07 11:31:59 -07:00
malloc_stats.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
manual_compaction_test.cc Remove using namespace (#9369) 2022-01-12 09:31:12 -08:00
memtable_list_test.cc MemTableList::TrimHistory now use allocated bytes (#9020) 2021-12-02 11:45:39 -08:00
memtable_list.cc Make MemoryAllocator into a Customizable class (#8980) 2021-12-17 04:20:47 -08:00
memtable_list.h Make MemoryAllocator into a Customizable class (#8980) 2021-12-17 04:20:47 -08:00
memtable.cc Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
memtable.h Make MemoryAllocator into a Customizable class (#8980) 2021-12-17 04:20:47 -08:00
merge_context.h Add Merge Operator support to WriteBatchWithIndex (#8135) 2021-05-10 12:50:25 -07:00
merge_helper_test.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
merge_helper.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
merge_helper.h Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
merge_operator.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
merge_test.cc Make the Env class Customizable (#9293) 2022-01-04 16:45:49 -08:00
obsolete_files_test.cc Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
options_file_test.cc No elide constructors (#7798) 2020-12-23 16:55:53 -08:00
output_validator.cc Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
output_validator.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
perf_context_test.cc Use SystemClock* instead of std::shared_ptr<SystemClock> in lower level routines (#8033) 2021-03-15 04:34:11 -07:00
periodic_work_scheduler_test.cc Fix a minor issue with initializing the test path (#8555) 2021-07-23 08:38:45 -07:00
periodic_work_scheduler.cc Use SystemClock* instead of std::shared_ptr<SystemClock> in lower level routines (#8033) 2021-03-15 04:34:11 -07:00
periodic_work_scheduler.h Add a SystemClock class to capture the time functions of an Env (#7858) 2021-01-25 22:09:11 -08:00
pinned_iterators_manager.h Replace most typedef with using= (#8751) 2021-09-07 11:31:59 -07:00
plain_table_db_test.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
pre_release_callback.h Fix and detect headers with missing dependencies (#8893) 2021-09-10 10:00:26 -07:00
prefix_test.cc Use SystemClock* instead of std::shared_ptr<SystemClock> in lower level routines (#8033) 2021-03-15 04:34:11 -07:00
range_del_aggregator_bench.cc Cleanup multiple implementations of VectorIterator (#8901) 2021-10-06 07:48:31 -07:00
range_del_aggregator_test.cc Cleanup multiple implementations of VectorIterator (#8901) 2021-10-06 07:48:31 -07:00
range_del_aggregator.cc In ParseInternalKey(), include corrupt key info in Status (#7515) 2020-10-28 10:12:58 -07:00
range_del_aggregator.h Fix some typos in comments (#8066) 2021-03-25 21:18:08 -07:00
range_tombstone_fragmenter_test.cc Cleanup multiple implementations of VectorIterator (#8901) 2021-10-06 07:48:31 -07:00
range_tombstone_fragmenter.cc Added memtable garbage statistics (#8411) 2021-06-18 04:57:27 -07:00
range_tombstone_fragmenter.h Added memtable garbage statistics (#8411) 2021-06-18 04:57:27 -07:00
read_callback.h Fix and detect headers with missing dependencies (#8893) 2021-09-10 10:00:26 -07:00
repair_test.cc Some fixes and enhancements to ldb repair (#8544) 2021-07-28 16:44:14 -07:00
repair.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
snapshot_checker.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
snapshot_impl.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
snapshot_impl.h Fix and detect headers with missing dependencies (#8893) 2021-09-10 10:00:26 -07:00
table_cache.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
table_cache.h Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
table_properties_collector_test.cc Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
table_properties_collector.cc Apply sample_for_compression to all block-based tables (#8105) 2021-03-25 15:00:45 -07:00
table_properties_collector.h Track each SST's timestamp information as user properties (#9093) 2021-11-19 11:37:06 -08:00
transaction_log_impl.cc Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
transaction_log_impl.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
trim_history_scheduler.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
trim_history_scheduler.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
version_builder_test.cc File temperature information should be preserved when restart the DB (#9242) 2021-12-03 14:43:14 -08:00
version_builder.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
version_builder.h Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
version_edit_handler.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
version_edit_handler.h Fixed manifest_dump issues when printing keys and values containing null characters (#8378) 2021-06-10 12:55:20 -07:00
version_edit_test.cc File temperature information should be preserved when restart the DB (#9242) 2021-12-03 14:43:14 -08:00
version_edit.cc Print file checksum in hex (#9196) 2021-11-22 09:30:47 -08:00
version_edit.h Recover to exact latest seqno of data committed to MANIFEST (#9305) 2022-01-05 16:02:21 -08:00
version_set_test.cc Add filename to several Corruption messages (#9239) 2022-01-07 18:09:48 -08:00
version_set.cc Fast path for detecting unchanged prefix_extractor (#9407) 2022-01-21 11:37:46 -08:00
version_set.h Remove obsolete function declaration (#8724) 2022-01-07 18:06:10 -08:00
wal_edit_test.cc Always track WAL obsoletion (#7759) 2020-12-09 16:02:12 -08:00
wal_edit.cc Always track WAL obsoletion (#7759) 2020-12-09 16:02:12 -08:00
wal_edit.h Always track WAL obsoletion (#7759) 2020-12-09 16:02:12 -08:00
wal_manager_test.cc Make SystemClock into a Customizable Class (#8636) 2021-09-21 09:23:48 -07:00
wal_manager.cc Allow WAL dir to change with db dir (#8582) 2021-07-30 12:16:44 -07:00
wal_manager.h Allow WAL dir to change with db dir (#8582) 2021-07-30 12:16:44 -07:00
write_batch_base.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
write_batch_internal.h Fix link error reported in issue 9272 (#9278) 2021-12-10 20:33:46 -08:00
write_batch_test.cc Add commit marker with timestamp (#9266) 2021-12-10 11:05:35 -08:00
write_batch.cc Fix link error reported in issue 9272 (#9278) 2021-12-10 20:33:46 -08:00
write_callback_test.cc Move slow valgrind tests behind -DROCKSDB_FULL_VALGRIND_RUN (#8475) 2021-07-07 11:14:05 -07:00
write_callback.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
write_controller_test.cc Revamp WriteController (#8064) 2021-03-18 09:47:31 -07:00
write_controller.cc Revamp WriteController (#8064) 2021-03-18 09:47:31 -07:00
write_controller.h Revamp WriteController (#8064) 2021-03-18 09:47:31 -07:00
write_thread.cc Stall writes in WriteBufferManager when memory_usage exceeds buffer_size (#7898) 2021-04-21 13:54:02 -07:00
write_thread.h typo: fix typo in db/write_thread's state (#8423) 2021-06-18 17:14:51 -07:00