> Sections 13 - 14.9 of the RFC 2616 HTTP 1.1 specification > > http://www.w3.org/Protocols/rfc2616/rfc2616.html > > <snip> > The Cache-Control general-header field is used to specify > directives that MUST be obeyed by all caching mechanisms > along the request/response chain </snip>
sure, but with desktop boxes in the basement of every joe sixpack, that's not going to help a lot, as these people connect without a caching mechanism between themselves and the site. So if they pull your sites content, the content is re-rendered. A second request will likely hit the browsercache, but it first has to get there. A caching mechanism on teh server avoids that re-render, it simply sends the cached output. Frans. > > > -----Original Message----- > From: Unmoderated discussion of advanced .NET topics. > [mailto:[EMAIL PROTECTED] On Behalf Of Frans Bouma > Sent: 12 October 2004 12:19 > To: [EMAIL PROTECTED] > Subject: Re: [ADVANCED-DOTNET] MiddleTier Caching was Abstracting SQL > > Isn't that caching header used to control proxy server caches? I.e.: > when 500,000 desktop boxes connect to your website, not > through a proxy, your pages will be rendered 500,000 times. I > think the poster was asking for a caching solution on the > webserver itself, so no matter what is used on the client > side (or the route to the client side) the server is not > under stess when the site receives a lot of requests > > Frans. > > > IIS5/6 are both capable of adding a cache-control header; > part of the > > HTTP > > 1.1 protocol - ASP.NET simply adds this header when using the > > OutputCache directive, to the outgoing HTTP stream - you may notice > > that static items, such as images etc are always cached by > default by > > the IE cache on the client. > > > > Using the cache-control headers it's possible to force > content to be > > cached in several locations, ranging from client, server and any > > intermediate point of presence server (ISP cache/proxy) in the > > internet. > > > > ASP was designed to serve dynamic content not static > content, such as > > HTML/images. It's normal practice to try and offload the serving of > > static content onto publishing servers i.e. > > caching servers e.g. ISA server - therefore allowing IIS/ASP to do > > what it's meant to i.e. serve dynamic content. > > > > Each virtual dir in IIS5/6 can be set to add cache-control headers > > (this does not require ASP.NET and can be used for any web > application > > including VB6, PHP etc) > > > > You can set the cache-control header by looking at the HTTP headers > > tab of your vdir - it's possible to set an absolute time out, or > > minutes, hours, days etc > > > > I hope this helps, but beware caching too much content can actually > > degrade system performance - the machine will use a larger > amount of > > resources and may take longer to look up the cached page it may be > > quicker to simply regenerating it from the originating server - you > > should test this before employing a caching strategy. > > > > Regards, > > Andrew > > > > Developmentor Instructor > > Course Author > > > > > > -----Original Message----- > > From: Unmoderated discussion of advanced .NET topics. > > [mailto:[EMAIL PROTECTED] On Behalf Of > Frans Bouma > > Sent: 12 October 2004 10:28 > > To: [EMAIL PROTECTED] > > Subject: Re: [ADVANCED-DOTNET] MiddleTier Caching was > Abstracting SQL > > > > > Frans Bouma wrote: > > > > To save webserver power because the website gets 500,000 > > > hits per day? > > > > Perhaps a page caching with 1 minute per page will help. > > Often that > > > > will give much more performance boosts than lowlevel > > caching with a > > > > lot of overhead. > > > > > > > This is what we often do, but when the cache invalidates, > > those 500000 > > > hits are wanting to update the cache and flood the db, I am > > > exaggerating but you catch my drift :D Any one ideas how > to prevent > > > the flooding of the db (in a VB6 world) ? > > > > If a page cache invalidates, the first request will hit the > > db, the second will get the cached version. > > > > But you can also use the system used by for example > slashdot. > > Say your webserver farm can render ALL the pages you want > caching for > > in 10 seconds. This means that if you re-render all these > pages every > > 20 seconds, your system will perform nicely no matter how many hits > > your system gets, although performance can degrade a little > when more > > requests come in. > > After the site is rendered, it is cached completely till the next > > re-render (which is using a render to cache mechanism) > > > > The beauty of the system is that when extra performance is > > required, you simply crank up the interval: > > not every 20 seconds, but every minute you do a re-render. > > > > Frans. > > > > =================================== > > This list is hosted by DevelopMentor. http://www.develop.com Some > > .NET courses you may be interested in: > > > > Essential .NET: building applications and components with CSharp > > August 30 - September 3, in Los Angeles > > http://www.develop.com/courses/edotnet > > > > View archives and manage your subscription(s) at > > http://discuss.develop.com > > > > =================================== > > This list is hosted by DevelopMentor(r) > http://www.develop.com Some > > .NET courses you may be interested in: > > > > Essential .NET: building applications and components with CSharp > > August 30 - September 3, in Los Angeles > > http://www.develop.com/courses/edotnet > > > > View archives and manage your subscription(s) at > > http://discuss.develop.com > > > > > > > > =================================== > This list is hosted by DevelopMentor. http://www.develop.com > Some .NET courses you may be interested in: > > Essential .NET: building applications and components with > CSharp August 30 - September 3, in Los Angeles > http://www.develop.com/courses/edotnet > > View archives and manage your subscription(s) at > http://discuss.develop.com > > =================================== > This list is hosted by DevelopMentor(r) http://www.develop.com > Some .NET courses you may be interested in: > > Essential .NET: building applications and components with > CSharp August 30 - September 3, in Los Angeles > http://www.develop.com/courses/edotnet > > View archives and manage your subscription(s) at > http://discuss.develop.com > > > =================================== This list is hosted by DevelopMentorŪ http://www.develop.com Some .NET courses you may be interested in: Essential .NET: building applications and components with CSharp August 30 - September 3, in Los Angeles http://www.develop.com/courses/edotnet View archives and manage your subscription(s) at http://discuss.develop.com