9ba7a0d955
Added new argument '-s' which takes additional argument composed of list of logfile identifiers. Logfiles listed with '-s' will be written on main memory instead of disk. In practice, the log file in question will be written in /dev/shm but corresponding symlink is added to log directory. In the case of name conflicts with log files and links, a differentiating sequence number is included in hte name of the file. This, however, is done only when existing file is not writable or is of different type (symlink <> file). Added new logfile LOGFILE_DEBUG whose contents will be largerly what was included up to date in trace log. Disabled feature which spreads writes to log files to others because of bug (#338) in the way block buffers are managed. Changed log manager parameters to match with the current implementation. List of arguments: "-h - help\n" "-a <debug prefix> ............(\"skygw_debug\")\n" "-b <debug suffix> ............(\".log\")\n" "-c <trace prefix> ............(\"skygw_trace\")\n" "-d <trace suffix> ............(\".log\")\n" "-e <message prefix> ............(\"skygw_msg\")\n" "-f <message suffix> ............(\".log\")\n" "-g <error prefix> ............(\"skygw_err\")\n" "-i <error suffix> ............(\".log\")\n" "-j <log path> ............(\"/tmp\")\n" "-s <shmem log file ids> ........(no default)\n"; dcb.c dcb_add_to_zombieslist, add dcb to the front of zombies list instead of inserting to the end of it. gateway.c Renamed shutdown_gateway to shutdown_server (Bug #131) Call skygw_logmanager_init so that trace and debug logs are written to shared memory. poll.c dcb.h Removed some dead code and references to unneeded mutexes. debugcmd.c Added enable/disable log command for debug log. skygw_utils.cc skygw_file_init now takes optional symlink name as a second argument. Symlink is created to point to the file being created.
/** \mainpage MaxScale by SkySQL The SkySQL MaxScale is an intelligent proxy that allows forwarding of database statements to one or more database server user complex rules and a semantic understanding of the database satements and the roles of the various servers within the backend cluster of databases. The MaxScale is designed to provided load balancing and high avilability functionality transparantly to the applications. In addition it provides a highly scalable and flexibile architecture, with plugin components to support differnt protocols and routing decissions. The MaxScale is implemented in C and makes entensive use of the asynchronous I/O capabilities of the Linux operating system. The epoll system is used to provide the event driven framework for the input and output via sockets. The protocols are implemented as external shared object modules which can be loaded and runtime. These modules support a fixed interface, communicating the entries points via a structure consisting of a set of function pointers. This structured is called the "module object". The code that routes the queries to the database servers is also loaed as external shared objects and are referred to as routing modules. \section Building Building the MaxScale Edit the file build_gateway.inc in your skygateway directory and set the ROOT_PATH and MARIADB_SRC_PATH variables to the location in which you checked out the code and the location of your MariaDB source. Build the libmysqld in $MARIADB_SRC_PATH Go to the sky gateway directory and do a make depend to update all the dependency files and then do a make. This should get you all the things built that you need. Other make targets are available install - Installs the binary and the modules in the location defined by the make variable DEST ctags - Build tags files for the vi editor documentation - Build the doxygen documentation depend - Update the dependencies used by the makefiles Two files are required for the libmysqld library that is used within MaxScale, /usr/local/mysql/share/english/errmsg,sys and a my.cnf file with the following: [mysqld] max_connections=4096 \section Running Running the MaxScale The gateway consists of a core executable and a number of modules that implement the different protocols and routing algorithms. These modules are built as shared objects that are loaded on demand. In order for the gateway to find these modules it will search using a predescribed search path. The rules are: 1. Look in the current directory for the module 2. Look in $MAXSCALE_HOME/modules 3. Look in /usr/local/skysql/MaxScale/modules Configuration is read by default from the file $MAXSCALE_HOME/etc/MaxScale.cnf, /etc/MaxScale.cnf, an example file is included in the root of the source tree. The default location can be overriden by use of the -c flag on the command line. This should be immediately followed by the path to the configuration file. */