The existing default value 1000 is too big and could result in
"hanging" when failing to connect a remote server. Three tries in
total is a more sensible default.
Remove the dead-code, in Spider, which is related to the Spider's
HandlerSocket support. The code has been disabled for a long time
and it is unlikely that the code will be enabled.
- rm all files under storage/spider/hs_client/ except hs_compat.h
- rm storage/spider/spd_db_handlersocket.*
- unifdef -UHS_HAS_SQLCOM -UHAVE_HANDLERSOCKET \
-m storage/spider/spd_* storage/spider/ha_spider.* storage/spider/hs_client/*
- remove relevant files from storage/spider/CMakeLists.txt
same assertion with spider. spider status variables
didn't expect to be queried from a different thread
without LOCK_thd_data.
And they didn't expect to be queried under LOCK_thd_data either
(because spider_get_trx() calls thd_set_ha_data()).
In commit b4ff64568c the
signature of mysql_show_var_func was changed, but not all functions
of that type were adjusted.
When the server is configured with `cmake -DWITH_ASAN=ON` and
compiled with clang, runtime errors would be flagged for invoking
functions through an incompatible function pointer.
Reviewed by: Michael 'Monty' Widenius
MDEV-27106 added REMOTE_TABLE, REMOTE_DATABASE, REMOTE_SERVER spider
table options. In this commit, we add all remaining options for table
params that are not marked to be deprecated.
All these options are parsed as strings from sql statements and have
string values at the sql level, so that we can determine whether it is
specified by checking its nullness.
The string values are further parsed by Spider into their actual types
in the SPIDER_SHARE, including string list, bounded nonnegative int,
bounded nonnegative int list, nonnegative longlong, boolean, and key
hints. Except for string lists, all other types are validated during
this parsing process.
Most of the options are backward compatible, i.e. they accept any
values that is accepted by there corresponding param parser. The only
exception is the index hint IDX which corresponds to the idxNNN param
name. For example,
'idx000 "f PRIMARY", idx001 "u k1"'
translates to
IDX="f PRIMARY u k1".
We include a test with all options specified, and tests involving
spider table options of all actual types.
Any table options, if present, will cause comments to be ignored with
a warning. The warning can be disabled by setting a new spider
global/session system variable spider_suppress_comment_ignored_warning
to 1.
Another global/session variable introduced is spider_ignore_comments,
which if set to 1, will cause COMMENT and CONNECTION strings to be
ignored unconditionally, whether or not table options are specified.
The MDEV-29693 conflict resolution is from Monty, as well as is
a bug fix where ANALYZE TABLE wrongly built histograms for
single-column PRIMARY KEY.
Also includes a fix for safe_malloc error reporting.
Other things:
- Copied main.log_slow from 10.4 to avoid mtr issue
Disabled test:
- spider/bugfix.mdev_27239 because we started to get
+Error 1429 Unable to connect to foreign data source: localhost
-Error 1158 Got an error reading communication packets
- main.delayed
- Bug#54332 Deadlock with two connections doing LOCK TABLE+INSERT DELAYED
This part is disabled for now as it fails randomly with different
warnings/errors (no corruption).
The system variable spider_disable_group_by_handler, if on, will
disable the spider group by handler (gbh), and such disablement serves
as workaround to bugs caused by gbh, labelled with spider-gbh on jira,
including MDEV-26247, MDEV-28998, MDEV-29163, MDEV-30392, MDEV-31645.
Tests for these tickets are added accordingly with the workaround in
place.
In particular:
* @@debug
deprecated since 5.5.37
* sr_YU locale
deprecated since 10.0.11
* "engine_condition_pushdown" in the @@optimizer_switch
deprecated since 10.1.1
* @@date_format, @@datetime_format, @@time_format, @@max_tmp_tables
deprecated since 10.1.2
* @@wsrep_causal_reads
deprecated since 10.1.3
* "parser" in mroonga table comment
deprecated since 10.2.11
The direct aggregate mechanism sems to be only intended to work when
otherwise a full table scan query will be executed from the spider
node and the aggregation done at the spider node too. Typically this
happens in sub_select(). In the test spider.direct_aggregate_part
direct aggregate allows to send COUNT statements directly to the data
nodes and adds up the results at the spider node, instead of iterating
over the rows one by one at the spider node.
By contrast, the group by handler (GBH) typically sends aggregated
queries directly to data nodes, in which case DA does not improve the
situation here.
That is why we should fix it by disabling DA when GBH is used.
There are other reasons supporting this change. First, the creation of
GBH results in a call to change_to_use_tmp_fields() (as opposed to
setup_copy_fields()) which causes the spider DA function
spider_db_fetch_for_item_sum_funcs() to work on wrong items. Second,
the spider DA function only calls direct_add() on the items, and the
follow-up add() needs to be called by the sql layer code. In
do_select(), after executing the query with the GBH, it seems that the
required add() would not necessarily be called.
Disabling DA when GBH is used does fix the bug. There are a few
other things included in this commit to improve the situation with
spider DA:
1. Add a session variable that allows user to disable DA completely,
this will help as a temporary measure if/when further bugs with DA
emerge.
2. Move the increment of direct_aggregate_count to the spider DA
function. Currently this is done in rather bizarre and random
locations.
3. Fix the spider_db_mbase_row creation so that the last of its row
field (sentinel) is NULL. The code is already doing a null check, but
somehow the sentinel field is on an invalid address, causing the
segfaults. With a correct implementation of the row creation, we can
avoid such segfaults.
The existing (incorrect) overriding mechanism is:
Non-minus-one var value overrides table param overrides default value.
Before MDEV-27169, unspecified var value is -1. So if the user sets
both the var to be a value other than -1 and the table param, the var
value will prevail, which is incorrect.
After MDEV-27169, unspecified var value is default value. So if the
user does not set the var but sets the table param, the default value
will prevail, which is even more incorrect.
This patch fixes it so that table param, if specified, always
overrides var value, and the latter if not specified or set to -1,
falls back to the default value
We achieve this by replacing all such overriding in spd_param.cc with
macros that override in the correct way, and removing all the
"overriding -1" lines involving table params in
spider_set_connect_info_default() except for those table params not
defined as sysvar/thdvar in spd_params.cc
We also introduced macros for non-overriding sysvar and thdvar, so
that the code is cleaner and less error-prone
In server versions where MDEV-27169 has not been applied, we also
backport the patch, that is, replacing -1 default values with real
default values
In server versions where MDEV-28006 has not been applied, we do the
same for udf params
Extracted out common subroutines, gave more meaningful names etc,
added comments etc.
Also:
- Documented active servers load balancing reads, and other fields in
SPIDER_SHARE etc.
- Removed commented out code
- Documented and refactored self-reference check
- Removed some unnecessary functions
- Renamed unhelpful roop_count
- Refactored spider_get_{sts,crd}, where we turn get_type into an enum
- Cleaned up spider_mbase_handler::show_table_status() and
spider_mbase_handler::show_index()
