web application architecture

Introduction To WebIntroduction To WebIntroduction To Web Introduction To Web Application ArchitectureApplication Architecturepppp

PRATIK PRATIK GohilGohilSr Lecturer SVICSSr Lecturer SVICS KadiKadiSr. Lecturer, SVICS, Sr. Lecturer, SVICS, [email protected]@gmail.comResources: p2gohil.blogspot.comResources: p2gohil.blogspot.com

Introduction To Web Application Architecture – PRATIK Gohil, SVICS, Kadi.

AgendaAgendaIIS 6.0 and IIS 6.0 and ASP.NetASP.Net ArchitectureArchitectureReliabilityReliabilityState ManagementState ManagementState ManagementState ManagementCachingCachingOth C l St ffOth C l St ffOther Cool StuffOther Cool Stuff


Rearchitecting IISRearchitecting IISA review of IIS5A review of IIS5

DLLHost.EXE

ISAPIDLLHost.EXEINETINFO.EXE

ExtensionsISAPI

Extensions

ISAPI Filters and Extensions DLLHost.EXE

ISAPI

WinSock 2 0

Metabase ISAPIExtensions

TCP/IPkernel

user WinSock 2.0


TCP/IP

IIS 6.0 ArchitectureIIS 6.0 Architecture

Goal: Enable complete appGoal: Enable complete appGoal: Enable complete app Goal: Enable complete app isolation from other Web isolation from other Web apps and core Web serverapps and core Web serverWeb service in INETINFOWeb service in INETINFO

WASWASW3wp.exeW3wp.exeW3wp.exeW3wp.exeW3wp.exeW3wp.exe

web web appapp

Web service in INETINFO Web service in INETINFO split out to do this:split out to do this:

Http.sys: Kernel mode Http.sys: Kernel mode li t d t tli t d t t

web web appapp

web web appappWeb Web

AppApplistener and request routerlistener and request routerWAS: Config and process WAS: Config and process managermanagerW3 Wh W bW3 Wh W b HttHttelel

AppApp

W3wp.exe: Where Web apps W3wp.exe: Where Web apps are processedare processed

Multiple W3wp.exe filesMultiple W3wp.exe files

Http.sysHttp.sysK

ern

Ker

n


Process Model ContrastProcess Model ContrastIIS5 to IIS6 IIS5 to IIS6 –– Making it more robustMaking it more robust

Worker Worker ProcessProcess



INETINFOINETINFO

AppPool 1AppPool 1 AppPool 2AppPool 2

RequestsRequestsApp2App2

ProcessProcess

App2App2

ProcessProcess

App1App1

ProcessProcess

WASWASmetabasemetabase

User Mode

Kernel Mode

FiltersFiltersFiltersFiltersFiltersFilters

HTTP.SYSHTTP.SYS TCP/IP TCP/IP ConnectionsConnections


ASP.Net on IIS 6ASP.Net on IIS 6NET Application Domains vs Application PoolsNET Application Domains vs Application Pools.NET Application Domains vs. Application Pools.NET Application Domains vs. Application Pools

Application domainsApplication domainsApplication PoolApplication PoolLightweight CLR unit of isolationLightweight CLR unit of isolation

One app domain per IIS applicationOne app domain per IIS applicationCombine with W3wp.exe files to Combine with W3wp.exe files to achie e high scalabilit and isolationachie e high scalabilit and isolation

W3wp.exeW3wp.exe

ASP NETASP NET

Application PoolApplication Pool

achieve high scalability and isolationachieve high scalability and isolationASP.NET manages app domains ASP.NET manages app domains independentlyindependently

Recycled within a single processRecycled within a single process

ASP.NETASP.NET

AppAppAppAppRecycled within a single processRecycled within a single process

Can have private components, Can have private components, session variables , etc.session variables , etc.

App poolApp pool

DomainDomainAppApp

DomainDomainAppApp

DomainDomainAppApp

DomainDomainAppApp

DomainDomainAppApp

DomainDomainAppApp

DomainDomainAppAppApp poolApp pool

W3wp.exeW3wp.exe

ASP.NETASP.NETWASWAS

DomainDomainDomainDomainW3wp.exeW3wp.exe

ASP.NETASP.NET


Http.sysHttp.sys

AgendaAgendaIIS 6.0 and ASP.Net ArchitectureIIS 6.0 and ASP.Net ArchitectureReliabilityReliabilityState ManagementState ManagementState ManagementState ManagementCachingCachingOth C l St ffOth C l St ffOther Cool StuffOther Cool Stuff


Application PoolsApplication PoolsApplication Isolation in ProcessesApplication Isolation in Processes

Can create 1 or moreCan create 1 or moreCan create 1 or more Can create 1 or more application poolsapplication pools

Each served by 1 or Each served by 1 or more processesmore processesmore processes.more processes.Each worker process Each worker process serves only 1 pool.serves only 1 pool.Reqs routed directly toReqs routed directly toReqs routed directly to Reqs routed directly to pool by HTTP.syspool by HTTP.sys

Isolate apps based Isolate apps based on:on:

Site/CustomerSite/CustomerFunctionalityFunctionality


FunctionalityFunctionalityReliabilityReliability

RecyclingRecyclingy gy gWhat is it and Why use it?What is it and Why use it?

What is it?What is it?What is it?What is it?Periodically restart Periodically restart applications based on:applications based on:

UptimeUptimeUptimeUptime# of requests# of requestsScheduled timeScheduled timeMemory consumptionMemory consumptiony py pOnOn--demanddemand

Why use it?Why use it?Refresh apps to ensureRefresh apps to ensureRefresh apps to ensure Refresh apps to ensure availabilityavailabilityPrevent bad apps from Prevent bad apps from taking over the systemtaking over the system


No interruption in No interruption in Service!!Service!!

RecyclingRecyclingOverlapping RecycleOverlapping Recycle

startupstartupreadyready

Old Worker Old Worker ProcessProcess

New Worker New Worker ProcessProcess

WAS

WAS

ProcessProcess

Web Proc. Web Proc. Core DLLCore DLL

Ready for Ready for RecycleRecycle

ProcessProcess

Web Proc. Web Proc. Core DLLCore DLL

Shut downShut down

user

ISAPI Exts &ISAPI Exts &FiltersFilters

ISAPI Exts &ISAPI Exts &FiltersFilters

kernelHTTP.SYSHTTP.SYS

Introduction To Web Application Architecture – PRATIK Gohil, SVICS, Kadi.RequestRequestRequestRequest

Increasing .NET Scale & PerformanceIncreasing .NET Scale & PerformanceAttributes of Scalable Web ApplicationsAttributes of Scalable Web ApplicationsAttributes of Scalable Web ApplicationsAttributes of Scalable Web Applications

StatelessStatelessStatelessStatelessApplication code and components can be Application code and components can be restarted cheaply; session state is restarted cheaply; session state is p y;p y;managed externally in some sort of state managed externally in some sort of state storestore

Low initialization costsLow initialization costsApplications should avoid doing heavyApplications should avoid doing heavyApplications should avoid doing heavy Applications should avoid doing heavy processing at startup or assume that they processing at startup or assume that they will run for a long timewill run for a long time


Increasing .NET Scale & PerformanceIncreasing .NET Scale & PerformanceAttributes of Scalable Web ApplicationsAttributes of Scalable Web Applications (2)(2)Attributes of Scalable Web ApplicationsAttributes of Scalable Web Applications (2)(2)

Can have multiple instancesCan have multiple instancesCan have multiple instancesCan have multiple instancesAll the components and classes of an All the components and classes of an application should be able to have multiple application should be able to have multiple pp ppp pinstances in separate processes without instances in separate processes without namespace or locking issuesnamespace or locking issues

Expect administratorExpect administrator--imposed limitsimposed limitsYour application is likely to haveYour application is likely to haveYour application is likely to haveYour application is likely to have

CPU limitsCPU limitsMemory limitsMemory limitsProcessor affinity imposedProcessor affinity imposed


Processor affinity imposedProcessor affinity imposed

Making Applications More ReliableMaking Applications More ReliableWeb Farm Session StateWeb Farm Session StateWeb Farm Session StateWeb Farm Session State

Session state can be stored in an externalSession state can be stored in an externalSession state can be stored in an external Session state can be stored in an external processprocess

ASPState Service ASPState Service MicrosoftMicrosoft®® SQL ServerSQL Server™™ 20002000

Big reliability wins Big reliability wins Session state survives crashes/restartsSession state survives crashes/restarts

Enables Web farm deploymentEnables Web farm deploymentS i t t b h d W bS i t t b h d W bSession state can now be shared across a Web Session state can now be shared across a Web farm of ASP.NET serversfarm of ASP.NET serversApplications no longer tied to one computerApplications no longer tied to one computer


Design your apps to be recycled!Design your apps to be recycled!

Dynamic Kernel CachingDynamic Kernel CachingWithWithWithoutWithout

CacheCache

WithWithCacheCache


RequestRequest ResponseResponse RequestRequest ResponseResponse

ASP.Net 2.0 Caching ImprovementsASP.Net 2.0 Caching ImprovementsData CachingData CachingData CachingData Caching

DataData--set based dataset based data--sources can be sources can be easily cachedeasily cached

Just set Just set EnableCachingEnableCaching to true on datato true on data--t lt lsource controlsource control

Also set Also set CacheDurationCacheDuration, , CacheExpirationPolicyCacheExpirationPolicy

SQL C h I lid ti f St l D tSQL C h I lid ti f St l D tSQL Cache Invalidation for Stale DataSQL Cache Invalidation for Stale DataSQL 7, 2000 use a custom change table, a SQL 7, 2000 use a custom change table, a DB trigger and a polling mechanism byDB trigger and a polling mechanism byDB trigger and a polling mechanism by DB trigger and a polling mechanism by ASP.NetASP.NetSQL 2005 uses Service BrokerSQL 2005 uses Service Broker


SQL 2005 uses Service BrokerSQL 2005 uses Service Broker

ASP.Net 2.0 Caching ImprovementsASP.Net 2.0 Caching ImprovementsPostPost Cache SubstituionCache SubstituionPostPost--Cache Substituion Cache Substituion

Output Cache an entire page except XXXOutput Cache an entire page except XXXXXX must be a simple stringXXX must be a simple string

Use Response.WriteSubstitution with Use Response.WriteSubstitution with callbackcallbackcallbackcallback

Or Use Substitution Control with Or Use Substitution Control with associated Callback methodassociated Callback method


Resource Optimization in IIS 6Resource Optimization in IIS 6Idle Timeout and Demand StartIdle Timeout and Demand StartIdle Timeout and Demand StartIdle Timeout and Demand Start

Idle timeoutIdle timeoutTimeout and shutdown idle processes if process isTimeout and shutdown idle processes if process isTimeout and shutdown idle processes if process is Timeout and shutdown idle processes if process is idle for given period of time.idle for given period of time.Frees resources for active applications.Frees resources for active applications.A till il bl if k idlA till il bl if k idlApps still available even if worker process idles Apps still available even if worker process idles out and is shut down! out and is shut down!

Demand startDemand startOnly start worker process if there is demand for Only start worker process if there is demand for the application pool. the application pool.

Application considerationsApplication considerationsApplication considerationsApplication considerationsUse idle timeout to free up resources for other Use idle timeout to free up resources for other heavyheavy--use applications.use applications.


Consider disabling idle timeout if starting an Consider disabling idle timeout if starting an application takes a long time.application takes a long time.

View State ImprovementsView State Improvements

More efficient More efficient i li i fi li i fserialization format serialization format

reduces state sizereduces state sizeSplitting View StateSplitting View StateSplitting View State Splitting View State into Control State into Control State and UI Stateand UI State


Site CompilationSite CompilationPrePre--Compile your websiteCompile your website

Use aspnet_compiler.exeUse aspnet_compiler.exeEndpoints reduced to empty files (aspx)Endpoints reduced to empty files (aspx)p p y ( p )p p y ( p )No requestNo request--time compilationtime compilation

/bin contains compiled assemblies for/bin contains compiled assemblies for/bin contains compiled assemblies for /bin contains compiled assemblies for entire siteentire site


web application architecture

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