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There"s more... generate, create none none for none projects iPhone MyISAM"s full- none for none text index has existed for several years, but has not been improved a great deal over time. If you have many concurrent requests you will notice significant resource usage, limiting scalability. Over the past few years, several third-party vendors have stepped up with alternative solutions to the problem of full-text search, offering more features and better performance.

One of those products, offering tight integration with MySQL and PHP, is Sphinx an open-source product available for free from

If you find that MySQL"s built-in capabilities are either too slow or too limited in other respects to meet your application"s requirements, you should definitely have a look at it.. Setting up new slaves in this scenario You should not none for none simply use a regular SQL dump to initialize the slave, as it will contain a create table statement that specifies InnoDB and does not include the full-text index. Of course, you could change the table type after the import is complete. However, this can be time consuming.

Instead, we recommend you first create the target schema on the slave, making sure the tables in question are created with ENGINE=MyISAM. Then go ahead and import the data into the table. Only after that, add the full-text index.

This is typically much faster than having the index in place beforehand because MySQL must then update it all the way through the bulk insert of rows. This is a very expensive operation compared to the delayed index creation..

1 . See also f Adding a full-text index in 2 Estimating network and slave I/O load Especially whe n using replication over a wide-area network connection with limited bandwidth, it is interesting to be able to predict the amount of data that needs to be transported between master and slaves. While MySQL does not use the most efficient strategy to deliver data, it is at least relatively easy to calculate the requirements in advance. This is less of a step-by-step recipe than an annotated walkthrough of the basic formula that can be used to estimate the traffic you will have to be prepared for.

. Getting ready In order to fo llow along, you must have some key data points available because otherwise there is not much to calculate. You will need: f The number of slaves (to be) connected to the master. f An idea about the average amount of binlogs written when using the master under regular load.

Knowing about peak times can be interesting as well. f The bandwidth of the connection between master and slaves. This includes the speed of the network interfaces on the master and, in general, the whole route between them (possibly including Internet connections).

We assume that there are no other network-intensive applications running on the master or slaves, so that practically all the speed your network card can provide is usable for MySQL. In this example, we will keep matters simple, assuming the following:. Data point Mas none for none ter"s Connectivity Slaves" Connectivity Value Gigabit LAN interface (approx. 100MB/s) 2MBit/s DSL line, of which 1MBit/s can be assumed available for MySQL. 1MBit/s comes down to approximately 100kb/s.

175MB per hour, approx. 50kb/s. 5 Master is connected to the Internet via a 10MBit/s connection, approx.

1MB/s.. Average amount of binlogs created on master Number of Slaves Speed of the slowest link in the connection between Master and Slaves.. Replication How to do it... 1. Check the m none none aster"s network speed: Multiply the number of slaves with the average amount of binlogs: 5x175MB/hour = 875MB/hour or about 250kb/second. The gigabit connection can handle this easily.

Check individual slaves" network speed: The 1MBit portion of the DSL line is sufficient for an average amount of data of 50kb/second. Often binlog production is not linear over time there might be peaks, but there is still a reserve. Check if the slowest part of the route between master and slaves can handle the load: 250kb/second should be no problem for the 10MBit/second Internet connection.

Disk I/O load on each slave, caused by the replication, is the amount of relay logs being written. This is equivalent to the amount of binlogs the master produces. Provided the slave"s I/O is not already saturated by other things, an additional 175MB per hour should not pose a problem either.

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