DAL is not doing a keepalive on connections but web2py in trunk will try 5 times to reopen closed connections.
On Apr 26, 10:21 am, Yarko Tymciurak <resultsinsoftw...@gmail.com> wrote: > On Apr 26, 2:17 am, annet <annet.verm...@gmail.com> wrote: > > > I came across this post: > > >http://groups.google.com/group/web2py/browse_thread/thread/82c1b8cdc1... > > > ... and read paragraph 6.1 and 6.2 of the manual. In paragraph 6.1 the > > connection strings reads like: > > > db = DAL('sqlite://storage.db', pool_size=0); the default. From > > 'Connection Pooling' I understand I'd better set the pool_size to for > > instance 10. In the group I also see connections pools of size 20. > > What's the best size to set the pool_size. > > "Best" is a performance issue. There is a nice writeup of the kinds > of "nuts and bolts" things involved (in general) > here:http://msdn.microsoft.com/en-us/library/8xx3tyca.aspx > > You can Google connection pooling (it can be handled at the db end, by > a db utility, at the ORM end - SqlAlchamy, for example, will keep > connections open). > > The question of what (if anything) DAL does at the DAL end, Massimo > would need to answer. > > I will say this: I had a "mere" 20 (very basic, it would seem) set > on Webfaction / Postgres. At some point (maybe 4 weeks back?), my > Postgres connections on webfaction started failing - simply being > denied. I took away the connection pooling argument in my web2py > app, and the connections resumed. > > This suggests: DAL is not holding connections open for us, it's > passing it on to the db; > Webfactional either ignored the pool requests, or has their own setup > and at some point denied if individual users tried to set any of the > parameters (I am really guessing here). > > In any case, "it depends" is the answer. ;-) > > - Yarko > > > > > Kind regards, > > > Annet.
