On Wed, 14 Apr 2004, Tim Cutts wrote: > > On 14 Apr 2004, at 10:57 pm, Adam Erickson wrote: > > > (This is probably not the best place for this post, but here goes...) > > > > The (soon to be released) MySQL cluster software docs use a "sample" > > cluster node configured with Dual Xeons and 16GB of ram. MySQL has > > never been able to use more than 2 gigs of system memory (on 32 bit > > platforms.) With MySQL Cluster, will MySQL finally start using the > > memory paging trick Oracle and others have been using for years? > > Otherwise, what is the point of having 16 gigs of ram for one MySQL > > server? > > Disk cache. Tables which MySQL doesn't have in its own buffers but > which nevertheless are frequently accessed will already be in RAM, and > therefore faster to access.
Well ... that doesn't tie in with what I'm reading about mysql cluster, namely it being a main memory database where all data is kept in memory. I guess you can probably run multiple instances of the cluster node on one machine, having the data split across them in a fairly transparent manner. However, there is ... very minimal technical information available on mysql.com about exactly what "mysql cluster" (ie. mysql on top of NDB) is and what it is really designed for. I looked at the NDB API docs in the bitkeeper tree, which help a bit ... but not all that much. It doesn't look like the current ndb code has any PAE support ... at least on Unix. It does some AWE-ish calls on windows but I don't think those are to actually allows more than somewhere between 2 and 4 gigs per process the way it is being used, unless I am missing something. My overview so far is that it is designed for very though transaction rate systems, with a large number of fairly simple transactions, and also possibly systems with a large amount of read activity. All of this needs to be on a moderately sized data set, since the design is based on it being an in memory database. In any case, since the NDB storage engine is used in place of myisam or innodb... even if it could address more memory using PAE, that wouldn't mean other storage engines could. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
