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c# - Usage of Server Side Controls in MVC Frame work -

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i using asp.net 4.0 , mvc 2.0 web application. project requiremrnt have use server side control in application not possibl in noraml case. ideally want use adrotator control , datalist control. i saw few samples , references in codepleax mvc controllib howwver found less useful. can tell how utilize theese controls in asp.net application along mvc. note: please provide functionalities related adrotator , datalist controls not equivalent functionalities thanks in advace. mvc pages not use normal .net solution makes use of normal .net components impossible. a normal .net page use event driven solution call different methods service side mvc use actions , view completly different way handle things. also, mvc not use viewstate normal .net controlls require. found article discussing mixing of normal .net , mvc.
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.net - multithreaded variable access -

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this question keeps haunting me: in multithreaded/multiprocessor environment - necessary use explicit locks synchronize access shared variables?

here scenario: have global variable pointing shared object. when instance of object created, reference placed in variable , becomes accessible other threads/processors.

the object immutable - once created never changes, because of multiple threads can access without additional synchronization.

once in while need update object. creating new instance of object on side , place reference new object in global variable.

so here question: can consider replacing reference atomic operation. in other words variable have valid reference object - either old 1 or new one?

is necessary use explicit locks synchronize access shared variables?

necessary? no. idea? yes. low-lock techniques hard right , justified. remember, lock slow when contested; if locks being contested, fix problem causing them contested, rather going low-lock solution.

the object immutable - once created never changes, because of multiple threads can access without additional synchronization.

awesome.

once in while need update object. creating new instance of object on side , place reference new object in global variable.

so here question: can consider replacing reference atomic operation. in other words variable have valid reference object - either old 1 or new one?

yes. c# specification guarantees operations on references atomic. however atomicity 1 small part of thread safety. atomicity merely guarantees every time @ variable, valid reference out of it. it not guarantee every time @ variable current reference out of it. nor guarantee any 2 threads see same sequence of changes in same order. nor guarantee two atomic updates 2 different variables seen in order happened on every thread. atomicity guarantees practically nothing, , might not guarantee enough make program work way think should.

my advice: if can avoid accessing variable on multiple threads, so. if cannot avoid it, put locks around it. if find performance reasons locks slow , cannot eliminate enough contention should consider going dangerous low-lock techniques making variable volatile, using interlocked exchanges, , on.


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