All prepare commands are executed in every backend server currently connected.
All executes are routed to master. If stmt type was recorded in prepare phase in rwsplit router, read-only stmts could be routed to slaves.
COM_STMT_PREPARE gets arbitrary number of response packets from backend database. Since statements are prepared in every backend server and only one multi-packet response can be replied to client, redundant multi-packet responses are discarded. This is done in router. Mechanisms from session command handling are utilized with little changes: router must identify when response consists of multiple packets so that it knows to calculate the number of packets in response and that it is able to discard correct number of packets.
Information to the reply-handling router is provided by backend protocol, which includes a ordered list of commands of commands sent to protocol-owning backend server. A command is stored to protocol struct in mysql_backend.c:gw_MySQLWrite_backend if the statement buffer's type has GWBUF_TYPE_SINGLE_STMT set in mysql_client.c:route_by_statement. GWBUF_TYPE_SINGLE_STATEMENT indicates that there is single statement in the buffer, as opposite to Read Connection router, which accepts streaming input from client.
Added a lot of logging to error, trace and message logs which should help the user to handle errors which can't be automatically resolved, like attempt to use nonexisting database.
query_classifier.cc use of uninitialized value in skygw_stmt_causes_implicit_commit
config.c crashed if module load failed, use of unitialized value
load_utils.c pretty-printed error
service.c use of uninitialized value in service_add_qualified_param
modules.h function prototype
readwritesplit.c memory leaks
1. in query_classifier.cc autocommit_enabled, and transaction_active variables maintained their values across different sessions. Now those values are stored in each router_client_ses object.
2. As a part of implementation of MAX-95 session variables were added to BACKEND struct which is shared with all sessions using the SERVICE which the particular BACKEND serves. Now each router_client_ses object has a backend reference struct which includes pointer to BACKEND, DCB and to session command cursor.
Added test - set_autocommit_disabled.sql, test_after_autocommit_disabled.sql - to check that session variable is discarded when session where it belongs terminates.
All tests are run by executing 'make testall' in root directory. As a result all directories which contain tests will be entered and tests executed.
After tests, each directory have a test log including the last run's logs only.
Created a global test log, which is specified in test.inc. Test logs from subdirectories are concatenated to this file.
Increased skygw_query_type_t to 16 bits, and corrected the way how those bit fields are checked.
Added tests for cases where autocommit is disabled and corrected old tests.
Every test/makefile have the following targets:
cleantests - clean local and subdirectories' tests
buildtests - build all local and subdirectories' tests
runtests - run all local tests
testall - clean, build and run local and subdirectories' tests
Tests for directory random_dir are always in its subdirectory, in this case in random_dir/test . If random_dir has subdirectories with tests, random_dir/child_dir, for example, tests of child_dir can be started from random_dir/test/makefile where make -C child_dir/test <test target> is called.
See MAXSCALE_HOME/test/README for further information.
Bug was identified by test, but it couldn't be validated. Using RW Split router currently may lead to situation where after setting system variable there is a backend server which doesn't have the value set. This is an incomplete feature at the moment rather than a bug.
dcb.c:dcb_write accept also dcb state DCB_STATE_NOPOLLING since it only means that dcb has been removed from epoll set but it is still possible to write to it.
Bug #384http://bugs.skysql.com/show_bug.cgi?id=384
session.h:added new state for SESSION, SESSION_STATE_ROUTER_READY which follows SESSION_STATE_READY. The difference is that ROUTER_READY is set only after router session is successfully created while READY means that session still lacks router.
session.c:set SESSION_STATE_ROUTER_READY when router is created.
mysql_backend.c:gw_read_backend_event, added SESSION_STATE_ROUTER_READY check before router session is closed. Changed chec kso that it doesn't block in infinite loop (although it shouldn't be possible anyway).
mysql_backend.c:gw_error_backend_event, added similar check before session is closed.
Removed MARIADB_SRC_PATH
Added MYSQL_ROOT - root directory where MariaDB headers are installed
Added MYSQL_HEADERS - -I notation for three header directories
Added EMBEDDED_LIB - for embedded library directory
Added ERRMSG - for errmsg.sys file
log_manager.cc
Little fixes
log_manager/makefile
Updated header include directive
makefile.inc
Removed DEBUGGER and BACKGR as unnecessary
Added LIB for embedded library file name
query_classifier/makefile
Updated header include directives and embedded library directory
query_classifier/query_classifier.cc
clean up
server/core/Makefile
Updated header include directives and embedded library directory
Added libaio and install of errmsg.sys
server/core/dcb.c
clean up
server/core/gateway.c
Added --language and --skip-innodb to mysql_library_init command-line arguments list
clean up
server/core/load_utils.c
clean up
server/modules/monitor/Makefile
server/modules/routing/readwritesplit/Makefile
Updated header include directives and embedded library directory
utils/skygw_debug.h
http://bugs.skysql.com/show_bug.cgi?id=369
utils/skygw_types.h
utils/skygw_utils.cc
clean up
Replaced fprintf's with log write commands, removed the second argument from call of mysql_reset_thd_for_next_command(thd) according to changes in mariadb/5.5/sql/sql_parse.c #rev 3958.
server/Makefile
Instead of installing MaxScale.cnf (and overwriting previous config file), install MaxScale_template.cnf to DEST directory.
config.c
Replace references to 'Gateway' with 'MaxScale', change configuration parameter 'auth' to 'passwd' as it is named in other instances where referenced to password.
resolve_query_type, added GSYSVAR_FUNC type for functions that read system variables and can be executed in Maxscale instead of backend server.
dcb.c
dcb_read, if read returns value <= 0 and if error is EAGAIN/EWOULDBLOCK so there was nothing to read in sthe socket, that is not an error because some other thread may have read the data that was expected to be available.
mysql_backend.c
gw_read_backend_event, used dcb->authlock to ensure that dcb's protocol state is read and modified serially. This removes issues with false authentication failures which may happen when two threads modify and read the state without any control.
mysql_client.c
removed dead code.
readconnroute.c, readwritesplit.c
removed invalid assert which assumed that spinlock can not have larger value than one when itis locked.
resolve_query_type, traverse through the list of items of thd->free_list, identify functions and reason query type according to the function type. This phase can only increase the restrictiviness level of the query.
query_classifier.h
Added new query type QUERY_TYPE_LOCAL_READ, for functions that can be executed in Maxscale. This type is the least restrict
ive query type. It is not used currently.
testmain.c
Added a few test cases and fixed expected return values for query type tests.
readwritesplit.c
polish
skygw_debug.h
Added string macro for Item types.
Removed embedded server startup parameter '--skip-innodb' and replaced TRUE, and FALSE with true and false, respectively.
gateway.c
Removed embedded server startup parameter '--skip-innodb' because libmysqld inside MariaDB 5.5.33 + doesn't start with that paramter.
