There were numerous memory leaks in plugin's code and associated code.
During typical run of MTR tests it leaked around 65 megabytes of
objects. As a result they may severely affect long-lived connections.
This patch fixes (almost) all leaks found in the plugin. The exceptions
are two leaks associated with SHOW CREATE TABLE columnstore_table and
getting information of columns of columnstore-handled table. These
should be fixed on the server side and work is on the way.
This patch improves handling of NULLs in textual fields in ColumnStore.
Previously empty strings were considered NULLs and it could be a problem
if data scheme allows for empty strings. It was also one of major
reasons of behavior difference between ColumnStore and other engines in
MariaDB family.
Also, this patch fixes some other bugs and incorrect behavior, for
example, incorrect comparison for "column <= ''" which evaluates to
constant True for all purposes before this patch.
* MCOL-4560 remove unused xml entries and code that references it.
There is reader code and variables for some of these settings, but nobody uses them.
* Fix clang warnings
* Remove vim tab guides
* initialize variables
* 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length
* Fix ISO C++17 does not allow 'register' storage class specifier for outdated bison
* chars are unsigned on ARM, having if (ival < 0) always false
* chars are unsigned by default on ARM and comparison with -1 if always true
Part 1:
As part of MCOL-3776 to address synchronization issue while accessing
the fTimeZone member of the Func class, mutex locks were added to the
accessor and mutator methods. However, this slows down processing
of TIMESTAMP columns in PrimProc significantly as all threads across
all concurrently running queries would serialize on the mutex. This
is because PrimProc only has a single global object for the functor
class (class derived from Func in utils/funcexp/functor.h) for a given
function name. To fix this problem:
(1) We remove the fTimeZone as a member of the Func derived classes
(hence removing the mutexes) and instead use the fOperationType
member of the FunctionColumn class to propagate the timezone values
down to the individual functor processing functions such as
FunctionColumn::getStrVal(), FunctionColumn::getIntVal(), etc.
(2) To achieve (1), a timezone member is added to the
execplan::CalpontSystemCatalog::ColType class.
Part 2:
Several functors in the Funcexp code call dataconvert::gmtSecToMySQLTime()
and dataconvert::mySQLTimeToGmtSec() functions for conversion between seconds
since unix epoch and broken-down representation. These functions in turn call
the C library function localtime_r() which currently has a known bug of holding
a global lock via a call to __tz_convert. This significantly reduces performance
in multi-threaded applications where multiple threads concurrently call
localtime_r(). More details on the bug:
https://sourceware.org/bugzilla/show_bug.cgi?id=16145
This bug in localtime_r() caused processing of the Functors in PrimProc to
slowdown significantly since a query execution causes Functors code to be
processed in a multi-threaded manner.
As a fix, we remove the calls to localtime_r() from gmtSecToMySQLTime()
and mySQLTimeToGmtSec() by performing the timezone-to-offset conversion
(done in dataconvert::timeZoneToOffset()) during the execution plan
creation in the plugin. Note that localtime_r() is only called when the
time_zone system variable is set to "SYSTEM".
This fix also required changing the timezone type from a std::string to
a long across the system.
1. Add a new system variable, columnstore_use_cpimport_for_cache_inserts,
that when set to ON, uses cpimport for the cache flush into ColumnStore.
This variable is set to OFF by default. By default, we perform batch inserts
for the cache flush.
2. Disable DMLProc logging of the SQL statement text for the cache
flush operation in case of batch inserts. Under certain heavy loads
involving INSERT statements, this logging becomes a bottleneck for
the cache flush, causing subsequent inserts into the cache table to hang.
1) Instead of making dbrm calls to writeVBEntry() per block,
we make these calls per batch. This can have non-trivial
reductions in the overhead of these calls if the batch size
is large.
2) In dmlproc, do not deserialize the whole insertpackage, which
consists of the complete record set per column, which would be
wasteful as we only need some metadata fields from insertpackage
here. This is only done for batch inserts at the moment, this
should also be applied to single inserts.
Fixes:
* Irrelevant where conditions
* Irrelevant const
* A potential infinite loop in treenode
* Bad implicit case fallthroughs
* Explicit markings for required case fallthroughs
* Unused variables
* Unused function
Also disabled some warnings for now which we should fix later.
Rename packages to MariaDB-columnstore-engine, MariaDB-columnstore-libs
and MariaDB-columnstore-platform.
Also add the "columnstore-" prefix the the components so that MariaDB's
packaging system understands then and add a line to include them in
MariaDB's packaging.
In addition
* Fix S3 building for dist source build
* Fix Debian 10 dependency issue
* Fix git handling for dist builds
* Add support for MariaDB's RPM building
* Use MariaDB's PCRE and readline
* Removes a few dead files
* Fix Boost noncopyable includes
I reformulate the messages.
Changed version in preprocessor conditions to avoid compilation
warnings in Debian 9.
Disabled sign-compare check for generated files in DML/DDL.
This changes the warning for truncation to the correct MariaDB error
code (1264).
In addition it passes the strict mode up into the DML class to roll back
correctly.
It also sets the abort_on_warning flag for updates as this isn't set on
the rnd_init phase but is needed for strict mode to work.
