WaffleGrid 0.4 "Butter"

We still have a long way to go but this should everyone a good technology preview.
Some risks to note:

*Their is a risk of a database crash if the memcached data is curropted ( i.e. bad packets/other weirdness )
*Full table scans are slower with waffle then non-waffle, we are looking into this
*You really need 1Gbe connection between the servers
*This is experimental... treat it as such
*In rare cases, it may casue the extinction of humanity...

other then that nothing else serious

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Grab MySQL 5.1.30
Grab Libmemcached
Grab memcached

If your using the patch:

root@bigdbahead:/opt/mysql-5.1.30-memscratch/storage# cat /home/matt/merge/wafflegrid-mysql-5.1.30.patch | patch -p0
patching file innobase/buf/buf0buf.c
patching file innobase/buf/buf0lru.c
patching file innobase/buf/buf0rea.c
patching file innobase/handler/ha_innodb.cc
patching file innobase/include/srv0srv.h
patching file innobase/include/srv0start.h
patching file innobase/include/thr0loc.h
patching file innobase/srv/srv0srv.c
patching file innobase/srv/srv0start.c
patching file innobase/thr/thr0loc.c

If your using the preview tarball your good, you have all the software.

on ubuntu you may need some of these packages... this is not a complete list and I may have some unneeded ones in here:
apt-get install bison byacc memcached libtool libncurses5 libncurses5-dev ncurses-base g++ gcc make libstatistics-descriptive-perl automake libevent-dev

Build the software:
Under the memcached directory
./configure
make
make install

under the libmemcached directory
./configure
make
make install

Under the mysql directory....

nohup ./BUILD/compile-pentium64-max-memc --prefix=/mysql > output 2>&1 &

*** note the prefix is the directory where you want to install mysql ****

make install

Setup the db environment just like a normal mysql installation ( will be installed in the --prefix location ), follow the standard mysql docs on this.

You should be good to go.

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Other notes:

Note here are the new my.cnf variables we introduced for waffle grid:

innodb_memcached_enable [ This can be 1 for on or 0 for off ]
innodb_memcached_servers [ This is not dynamic in this version, use a comma seperated list ie. 10.1.1.3,10.1.1.3:11212 ]
innodb_print_memcached_stats [ 0 for off, 1 for summary logging, 2 for detailed logging ... output goes to the error log ]
innodb_enable_rnd_readahead [ default is 1, which means random read ahead is enabled, disabling this may yeild benefits in some apps ]
innodb_enable_seq_readahead [ default is 1, which means sequential read ahead is enabled, disabling this may yeild benefits in some apps ]

After starting the database:

set @@global.innodb_memcached_enable=1;

Here is a sample config:

[mysqld]
user = mysql
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
port = 3306
basedir = /mysql/
datadir = /mysql/data
tmpdir = /tmp
skip-external-locking
innodb_memcached_servers=localhost
bind-address = 127.0.0.1
key_buffer = 64M
max_allowed_packet = 16M
thread_stack = 192K
thread_cache_size = 64
table_cache = 64
innodb_data_home_dir = /mysql/data
innodb_log_file_size = 128M
innodb_lock_wait_timeout = 50
innodb_buffer_pool_size = 768M
innodb_additional_mem_pool_size = 20M
innodb_log_buffer_size = 16M
innodb_flush_log_at_trx_commit = 0
innodb_flush_method = O_DIRECT
innodb_log_files_in_group = 2
innodb_data_file_path = ibdata1:500M:autoextend
innodb_support_xa = 0
innodb_thread_concurrency = 0