database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-29 05:21:33 +03:00
Code Activity

Windows improvements : manual backport of

Browse Source 
htttp://lists.mysql.com/commits/50957?f=plain
      
Always use TLS functions instead of __declspec(thread) to access 
thread local storage variables.
The change removes the necessity to recomplile the same source
files twice -  with USE_TLS for DLLs and without USE_TLS for EXEs.
Real benefit of this change is better readability and maintainability
of TLS functions within MySQL.
              
There is a performance loss using TlsXXX functions compared to __declspec 
but the difference is negligible in practice. In a sysbench-like benchmark 
I ran with with TlsGetValue, pthread_[get|set]_specific was called 600000000 
times and took 0.17sec of total 35min CPU time, or 0.008%.
This commit is contained in:
Vladislav Vaintroub
2009-09-30 03:22:57 +02:00
parent 28a7d5042b
commit 2bc1930c6c
8 changed files with 15 additions and 87 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
libmysql/CMakeLists.txt
View File

@ -100,29 +100,13 @@ SET(CLIENT_SOURCES ../mysys/array.c ../strings/bchange.c ../strings/bmove.c
../vio/viossl.c ../vio/viosslfactories.c ../strings/xml.c ../mysys/mf_qsort.c
../mysys/my_getsystime.c ../mysys/my_sync.c ../mysys/my_winerr.c ../mysys/my_winfile.c ${LIB_SOURCES})
# Need to set USE_TLS for building the DLL, since __declspec(thread)
# approach to thread local storage does not work properly in DLLs.
#
# The static library might be used to form another DLL, as is the case
# with the ODBC driver, so it has to be compiled with USE_TLS as well.
#
# We create a third library without USE_TLS for internal use. We can't
# be sure that some client application part of this build doesn't go
# beond the documented API, and try access the Thread Local Storage.
# The "_notls" means no Tls*() functions used, i.e. "static" TLS.
ADD_LIBRARY(mysqlclient STATIC ${CLIENT_SOURCES})
ADD_DEPENDENCIES(mysqlclient GenError)
TARGET_LINK_LIBRARIES(mysqlclient)
ADD_LIBRARY(mysqlclient_notls STATIC ${CLIENT_SOURCES})
ADD_DEPENDENCIES(mysqlclient_notls GenError)
TARGET_LINK_LIBRARIES(mysqlclient_notls)
ADD_LIBRARY(libmysql SHARED ${CLIENT_SOURCES} dll.c libmysql.def)
IF(WIN32)
SET_TARGET_PROPERTIES(libmysql mysqlclient PROPERTIES COMPILE_FLAGS "-DUSE_TLS")
ENDIF(WIN32)
ADD_DEPENDENCIES(libmysql GenError)
TARGET_LINK_LIBRARIES(libmysql wsock32)