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TiDB 5.2.2 Release Notes
Release Date: October 29, 2021
TiDB version: 5.2.2
Improvements
TiDB
TiKV
PD
- Add more types of write queries to QPS dimensions in the hotspot scheduler #3869
- Support dynamically adjusting the retry limit of the balance region scheduler to improve the performance of the scheduler #3744
- Update TiDB Dashboard to v2021.10.08.1 #4070
- Support that the evict leader scheduler can schedule regions with unhealthy peers #4093
- Speed up the exit process of schedulers #4146
Tools
TiCDC
- Reduce the default value of the Kafka sink configuration item
MaxMessageBytes
from 64 MB to 1 MB to fix the issue that large messages are rejected by the Kafka Broker #3104 - Reduce memory usage in the relpication pipeline #2553#3037 #2726
- Optimize monitoring items and alert rules to improve observability of synchronous links, memory GC, and stock data scanning processes #2735 #1606 #3000 #2985 #2156
- When the sync task status is normal, no more historical error messages are displayed to avoid misleading users #2242
- Reduce the default value of the Kafka sink configuration item
Bug Fixes
TiDB
- Fix the issue that plan-cache cannot detect changes of unsigned flags #28254
- Fix the wrong partition pruning when the partition function is out of range #28233
- Fix the issue that planner might cache invalid plans for
join
in some cases #28087 - Fix wrong index hash join when hash column type is enum #27893
- Fix a batch client bug that recycling idle connection might block sending requests in some rare cases #27688
- Fix the TiDB Lightning panic issue when it fails to perform checksum on a target cluster #27686
- Fix wrong results of the
date_add
anddate_sub
functions in some cases #27232 - Fix wrong results of the
hour
function in vectorized expression #28643 - Fix the authenticating issue when connecting to MySQL 5.1 or an older client version #27855
- Fix the issue that auto analyze might be triggered out of the specified time when a new index is added #28698
- Fix a bug that setting any session variable invalidates
tidb_snapshot
#28683 - Fix a bug that BR is not working for clusters with many missing-peer regions #27534
- Fix the unexpected error like
tidb_cast to Int32 is not supported
when the unsupportedcast
is pushed down to TiFlash #23907 - Fix the issue that
DECIMAL overflow
is missing in the%s value is out of range in '%s'
error message #27964 - Fix a bug that the availability detection of MPP node does not work in some corner cases #3118
- Fix the
DATA RACE
issue when assigningMPP task ID
#27952 - Fix the
INDEX OUT OF RANGE
error for a MPP query after deleting an emptydual table
. #28250 - Fix the issue of false positive error log
invalid cop task execution summaries length
for MPP queries #1791 - Fix the issue of error log
cannot found column in Schema column
for MPP queries #28149 - Fix the issue that TiDB might panic when TiFlash is shuting down #28096
- Remove the support for insecure 3DES (Triple Data Encryption Algorithm) based TLS cipher suites #27859
- Fix the issue that Lightning connects to offline TiKV nodes during pre-check and causes import failures #27826
- Fix the issue that pre-check cost too much time when importing many files to tables #27605
- Fix the issue that rewriting expressions makes
between
infer wrong collation #27146 - Fix the issue that
group_concat
function did not consider the collation #27429 - Fix the result wrong that occurs when the argument of the
extract
function is a negative duration #27236 - Fix the issue that creating partition fails if
NO_UNSIGNED_SUBTRACTION
is set #26765 - Avoid expressions with side effects in column pruning and aggregation pushdown #27106
- Remove useless gRPC logs #24190
- Limit the valid decimal length to fix precision-related issues #3091
- Fix the issue of a wrong way to check for overflow in
plus
expression #26977 - Fix the issue of
data too long
error when dumping statistics from the table withnew collation
data #27024 - Fix the issue that the retried transactions' statements are not included in
TIDB_TRX
#28670
TiKV
- Fix the issue that CDC adds scan retries frequently due to the Congest error #11082
- Fix the issue that the raft connection is broken when the channel is full #11047
- Fix the issue that batch messages are too large in Raft client implementation #9714
- Fix the issue that some coroutines leak in
resolved_ts
#10965 - Fix a panic issue that occurs to the coprocessor when the size of response exceeds 4 GiB #9012
- Fix the issue that snapshot Garbage Collection (GC) misses GC snapshot files when snapshot files cannot be garbage collected #10813
- Fix a panic issue caused by timeout when processing Coprocessor requests #10852
PD
- Fix the issue that PD incorrectly delete the peers with data and in pending status because the number of peers exceeds the number of configured peers #4045
- Fix the issue that PD does not fix down peers in time #4077
- Fix the issue that the scatter range scheduler cannot schedule empty regions #4118
- Fix the issue that the key manager cost too much CPU #4071
- Fix the data race issue that might occur when setting configurations of hot region scheduler #4159
- Fix slow leader election caused by stuck region syncer#3936
TiFlash
- Fix the issue that TiFlash fails to start up on some platforms due to the absence of library
nsl
- Fix the issue that TiFlash fails to start up on some platforms due to the absence of library
Tools
TiCDC
- Fix the issue that TiCDC replication task might terminate when the upstream TiDB instance unexpectedly exits #3061
- Fix the issue that TiCDC process might panic when TiKV sends duplicate requests to the same Region #2386
- Fix unnecessary CPU consumption when verifying downstream TiDB/MySQL availability #3073
- Fix the issue that the volume of Kafka messages generated by TiCDC is not constrained by
max-message-size
#2962 - Fix the issue that TiCDC sync task might pause when an error occurs during writing a Kafka message #2978
- Fix the issue that some partitioned tables without valid indexes might be ignored when
force-replicate
is enabled #2834 - Fix the issue that scanning stock data might fail due to TiKV performing GC when scanning stock data takes too long #2470
- Fix a possible panic issue when encoding some types of columns into Open Protocol format #2758
- Fix a possible panic issue when encoding some types of columns into Avro format #2648
TiDB Binlog
- Fix the issue that when most tables are filtered out, checkpoint can not be updated under some special load #1075
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