On Mon, Apr 10, 2006 at 05:22:13PM +0800, Qingqing Zhou wrote: > > "Markus Schiltknecht" <[EMAIL PROTECTED]> wrote > > Hi Qingqing, > > > > > > > > As Tom pointed out, without big change, a backend on database "D1" can't > > > connect to "D2". This is because to connect to a database, we need to > > > initialize a lot of variables. So when you reconnect to another one on > the > > > fly, you have to change these variables one by one. > > > > Sure, the question is: what is needed to retarget a backend? > > > Check the code InitPostgres(). These global varaibles are scattered in many > places, so I am not sure if it is easy to write clean code to clear up these > variables. But if you can come up with a patch to do reconnect without > disconnect, that will be cool.
Something else to consider: most queries that would benefit from parallel execution are expensive enough that the cost of spawning some new backends wouldn't be that big a deal, so perhaps for an initial version it would be best to KISS and just spawn parallel execution backends as needed. -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461 ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
