On 20/11/2007, Imri Zvik <[EMAIL PROTECTED]> wrote:
> Hi,
>
> The MySQL cluster can run perfectly on one physical node.
>
> The 3 nodes you're referring to are at least 1 management node, and at
> least 1 API ("mysqld") node, and at least 1 data/storage ("ndbd") node.
> They can all reside on the same physical node.All the How-To's I found about this say that the three nodes requirement is more about having at least two NDB "data" nodes to fail over between and an independent cluster-manager node which needs to actually do the fail-over. It can't sit on any of the "data nodes" and be HA because it must be able to run when the nodes become unavailable. You can pretend to have HA with less nodes but if the cluster manager doesn't run the fail-over won't happen. At least that's the gist of what I understood from skimming over the HOW-TO's. > > The main issue with NDB version 5.0 (from my point of view) is that it > must load all data into memory at runtime, so if your database is larger > than your amount of RAM, you better find some other solution, or split > it to enough replicas (data nodes) so that each chunk would fit. You mean replicas or maybe you meant to say "partitions", i.e. being able to split one database across multiple partitions? To broaden the above questions - how do you define "all data"? The entire database? The relevant partition? In any case, your comment above gives more than a hint about the NDB memory requirements. I've printed the white paper from MySQL's web site (http://www.mysql.com/why-mysql/white-papers/mysql_cluster_eval_guide.php) and I hope to get back to you with what I learn from it soon. > This problem is going to be solved with 5.1, but it is not even near > being production-ready (at least last time I've checked). Thanks. That gives perspective on where I stand regarding using it. Cheers, --Amos ================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
