Omitted new checks which produce too many matches or which are
controversial (e.g. readability-identifier-length).
New checks:
- misc-misleading-bidirectional + misc-misleading-identifier
Detects potential attack as described in the Trojan Source attack
- modernize-macro-to-enum
Replaces groups of adjacent macros with an unscoped anonymous enum
- modernize-shrink-to-fit
Replace copy and swap tricks on shrinkable containers with the
shrink_to_fit() method call
- modernize-use-transparent-functors
Prefer transparent functors to non-transparent ones
- modernize-use-uncaught-exceptions
This check will warn on calls to std::uncaught_exception and replace
them with calls to std::uncaught_exceptions (uncaught_exception was
deprecated with C++17)
- performance-no-int-to-ptr
Diagnoses every integer to pointer cast
- readability-duplicate-include
Looks for duplicate includes and removes them
- readability-redundant-preprocessor
Finds potentially redundant preprocessor directives
- bugprone-lambda-function-name
Checks for attempts to get the name of a function from within a lambda
expression
- bugprone-redundant-branch-condition
Finds condition variables in nested if statements that were also
checked in the outer if statement and were not changed
- bugprone-shared-ptr-array-mismatch
Finds initializations of C++ shared pointers to non-array type that
are initialized with an array
- bugprone-stringview-nullptr
Checks for various ways that the const CharT* constructor of
std::basic_string_view can be passed a null argument and replaces them
with the default constructor in most cases
- bugprone-suspicious-memory-comparison
Finds potentially incorrect calls to memcmp() based on properties of
the arguments
The original motivation for this commit was that shared_ptr_helper used
std::shared_ptr<>() which does two heap allocations instead of
make_shared<>() which does a single allocation. Turned out that
1. the affected code (--> Storages/) is not on a hot path (rendering the
performance argument moot ...)
2. yet copying Storage objects is potentially dangerous and was
previously allowed.
Hence, this change
- removes shared_ptr_helper and as a result all inherited create() methods,
- instead, Storage objects are now created using make_shared<>() by the
caller (for that to work, many constructors had to be made public), and
- all Storage classes were marked as noncopyable using boost::noncopyable.
In sum, we are (likely) not making things faster but the code becomes
cleaner and harder to misuse.
The check is currently *not* part of .clang-tidy. It complains about:
(1) "switch has multiple consecutive identical branches"
(2) "repeated branch in conditional chain"
About (1): Lots of findings in switches were about redundant
"[[fallthrough]]" in places where the compiler would not warn anyways. I
have cleaned these up.
About (2): In if-else_if-else chains, fixing the warning would usually
mean concatenating multiple if-conditions. As this would reduce
readability in most cases, I did not fix these places.
Because of (2), I also refrained from adding "bugprone-branch-clone" to
.clang-tidy.
From the log:
2022.04.29 12:33:40.397528 [ 486 ] {} <Debug> SystemLog (system.asynchronous_metric_log): Existing table system.asynchronous_metric_log for system log has obsolete or different structure. Renaming it to asynchronous_metric_log_352.
Old: CREATE TABLE system.asynchronous_metric_log (`event_date` Date CODEC(Delta(2), ZSTD(1)), `event_time` DateTime CODEC(Delta(4), ZSTD(1)), `metric` LowCardinality(String) CODEC(ZSTD(1)), `value` Float64 CODEC(Gorilla, ZSTD(3))) ENGINE = MergeTree PARTITION BY toYYYYMM(event_date) ORDER BY (metric, event_date, event_time) SETTINGS index_granularity = 8192
New: CREATE TABLE system.asynchronous_metric_log (`event_date` Date CODEC(Delta(2), ZSTD), `event_time` DateTime CODEC(Delta(4), ZSTD), `metric` LowCardinality(String) CODEC(ZSTD), `value` Float64 CODEC(Gorilla, ZSTD(3))) ENGINE = MergeTree PARTITION BY toYYYYMM(event_date) ORDER BY (metric, event_date, event_time) SETTINGS index_granularity = 8192
As you can see the difference in default ZSTD level.
P.S. I decided not to fix the printer, since this may introduce changes
in metadata, that may lead to changes in metadata between ZooKeeper and
clickhouse server.
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
Before it does lots of extra work, now, it will be significantly more
optimal (thousands of rows -> 1-2 million of rows).
v2: s/executeOnBlockSimple/executeOnBlockSmall/
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
This statistics significantly decrease performance of
optimize_aggregation_in_order with a prefix key.
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
