I'm talking CFMX, and this example illustrates my point exactly. The server CAN'T do the job of CFLOCK for situations exactly like this, so you (the developer) have to use it, or some other locking mechanism. Whether the server protects it's own memory or not isn't a big deal, it's whether the values in memory are valid.
--- Barney Boisvert, Senior Development Engineer AudienceCentral (formerly PIER System, Inc.) [EMAIL PROTECTED] voice : 360.756.8080 x12 fax : 360.647.5351 www.audiencecentral.com > -----Original Message----- > From: S. Isaac Dealey [mailto:[EMAIL PROTECTED] > Sent: Tuesday, April 01, 2003 4:21 PM > To: CF-Talk > Subject: RE: Is there a trick... > > > I'm guessing that they actually mean "if your variables get hozed as a > result of not locking it's happening because of a race condition > of your own > making". Rather than "data in the shared scopes may be randomly > corrupted if > not locked". For instance -- if you have a frameset that loads 2 > frames and > you need to set an application or session var before frame2 loads, but you > set it in the template loading in frame1 there's a chance it might not get > set until after frame2 loads and thereby frame2 would contain the > wrong data > -- but not through any fault of the server. This is probably a > poor example, > but at the moment it's the best I can do. :) > > > I interpret that paragraph as "The app server won't dump > > core if you don't > > lock your shared access, but your variable might get > > hosed." So, if you > > don't mind your variables possibly getting wasted, then > > yes, I'll agree that > > locking is optional. > > > barneyb > > > --- > > Barney Boisvert, Senior Development Engineer > > AudienceCentral (formerly PIER System, Inc.) > > [EMAIL PROTECTED] > > voice : 360.756.8080 x12 > > fax : 360.647.5351 > > > www.audiencecentral.com > > >> -----Original Message----- > >> From: Matthew Walker [mailto:[EMAIL PROTECTED] > >> Sent: Tuesday, April 01, 2003 3:27 PM > >> To: CF-Talk > >> Subject: RE: Is there a trick... > >> > >> > >> Pretty sure. The docs: > >> > >> While the ColdFusion Server is thread-safe and does not > >> try to modify a > >> variable simultaneously, it does not ensure the correct > >> order of access to > >> information. If multiple pages, or multiple invocations > >> of a page, attempt > >> to write data simultaneously, or read and write it at the > >> same time, the > >> resulting data can be inconsistent, as illustrated in the > >> following Sample > >> locking scenarios section. > >> > >> It doesn't say "thread-safe except if you try to access > >> application and > >> server scopes". > >> > >> Yes you still have to lock them. But CFMX does it > >> automatically, so you > >> don't have to do it explicitly. > >> > > >> > >> > >> > -----Original Message----- > >> > From: Barney Boisvert > >> > [mailto:[EMAIL PROTECTED] > >> > Sent: Wednesday, 2 April 2003 11:17 a.m. > >> > To: CF-Talk > >> > Subject: RE: Is there a trick... > >> > > >> > Are you sure about this? It is my understanding that > >> > the session scope > >> > was > >> > protected automatically, but that the application (and > >> > server) > >> scope still > >> > had to be locked. You can avoid having to do read > >> > locks with > >> CFLOCK on a > >> > scope if you ensure that they are never written after > >> > initially set, and > >> > that every request ensures that they are set before > >> > proceeding, but you > >> > still have to lock them in one form or another > >> > > >> > barneyb > >> > > >> > --- > >> > Barney Boisvert, Senior Development Engineer > >> > AudienceCentral (formerly PIER System, Inc.) > >> > [EMAIL PROTECTED] > >> > voice : 360.756.8080 x12 > >> > fax : 360.647.5351 > >> > > >> > www.audiencecentral.com > >> > > >> > > -----Original Message----- > >> > > From: Matthew Walker > >> > > [mailto:[EMAIL PROTECTED] > >> > > Sent: Tuesday, April 01, 2003 3:00 PM > >> > > To: CF-Talk > >> > > Subject: RE: Is there a trick... > >> > > > >> > > > >> > > Automatic locking. Previously you needed to write > >> > > > >> > > <cflock timeout="1" throwontimeout="No" > >> > > type="READONLY" > >> > > scope="APPLICATION"> > >> > > [do something with app variables] > >> > > </cflock> > >> > > > >> > > Many people got around this by simply copying the > >> > > application > >> > > scope into the > >> > > request scope in Application.cfm or thereabouts. > >> > > Others simply > >> > > wrote lots of > >> > > constants directly into the request scope on each > >> > > page request > >> > > (which isn't > >> > > nearly as slow as you might think). > >> > > > >> > > With CFMX you don't need to lock access to scopes > >> > > like application and > >> > > session. > >> > > > >> > > > -----Original Message----- > >> > > > From: Calvin Ward [mailto:[EMAIL PROTECTED] > >> > > > Sent: Wednesday, 2 April 2003 10:47 a.m. > >> > > > To: CF-Talk > >> > > > Subject: Re: Is there a trick... > >> > > > > >> > > > Isaac, > >> > > > > >> > > > What's the benefit that CFMX offers in the > >> > > > Application scope? > >> > > > > >> > > > Calvin > >> > > > > >> > > > <cf_snipalot /> > >> > > > > >> > > > > You'll be needlessly accessing the application > >> > > > > scope anyway. The > >> > > > application > >> > > > > scope should really only be used for data which > >> > > > > might change > >> > > > periodically > >> > > > > based on time of day, administrative interraction > >> > > > > (i.e. "this > >> > > feature is > >> > > > > currently unavailable due to maintenance"), or to > >> > > > > refresh > >> a cacheing > >> > > > > routine, etc. Data which is set, static and > >> > > > > required on every page > >> > > > should > >> > > > be > >> > > > > set solely in the request scope, unless you're > >> > > > > running CFMX > >> > > and planning > >> > > > to > >> > > > > access it directly from the application scope -- > >> > > > > which I > >> prefer not > >> > to > >> > > > do > >> > > > > because imho there's no real benefit over using > >> > > > > the request > >> > > scope while > >> > > > > there are definite advantages to using the > >> > > > > request scope > >> if you end > >> > up > >> > > > > needing backward compatibility for CF 5. > >> > > > > > >> > > > > hth > >> > > > > > >> > > > > > >> > > > > s. isaac dealey 954-776-0046 > >> > > > > > >> > > > > new epoch > >> > > > > http://www.turnkey.to > >> > > > > > >> > > > > lead architect, tapestry cms > >> > > > > http://products.turnkey.to > >> > > > > > >> > > > > tapestry api is opensource > >> > > > > http://www.turnkey.to/tapi > >> > > > > > >> > > > > certified advanced coldfusion 5 developer > >> > > > > http://www.macromedia.com/v1/handlers/index.cfm?I > >> > > > > D=21816 > >> > > > > > >> > > > > >> > > > > >> > > > >> > > >> > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > ~~~~~~~~~~~| > > Archives: > > http://www.houseoffusion.com/cf_lists/index.cfm?forumid=4 > > Subscription: http://www.houseoffusion.com/cf_lists/index. > > cfm?method=subscribe&forumid=4 > > FAQ: http://www.thenetprofits.co.uk/coldfusion/faq > > Get the mailserver that powers this list at > > http://www.coolfusion.com > > > Unsubscribe: http://www.houseoffusion.com/cf_lists/uns > ubscribe.cfm?user=633.558.4 s. isaac dealey 954-776-0046 new epoch http://www.turnkey.to lead architect, tapestry cms http://products.turnkey.to tapestry api is opensource http://www.turnkey.to/tapi certified advanced coldfusion 5 developer http://www.macromedia.com/v1/handlers/index.cfm?ID=21816 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Archives: http://www.houseoffusion.com/cf_lists/index.cfm?forumid=4 Subscription: http://www.houseoffusion.com/cf_lists/index.cfm?method=subscribe&forumid=4 FAQ: http://www.thenetprofits.co.uk/coldfusion/faq Your ad could be here. 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