asp.net mvc - Where does the worker thread come from on an async MVC action? -



asp.net mvc - Where does the worker thread come from on an async MVC action? -

imagine action:

public async task<actionresult> myaction(){ var result = await mymethodasync(); homecoming view(result); }

understand making action async, release thread executing action thread pool while mymethodasync() executes, can used serve other http requests. i'm wondering: thread executes mymethodasync()? i'm guessing it's not thread thread pool, since defeat purpose of async actions. brand new thread created, started , destroyed when http response finished?

no still comes thread pool, , not defeat purpose.

async comes becomes valuable during blocking operations, accessing disk or network, not cpu-bound (i.e., operations i/o (input/output) bound).

the thread returned pool doesn't have wait blocking operation finish before can help service http request.

once blocking operation complete, worker thread grabbed from pool.

this can help counteract called thread pool starvation. each thread pool spins many threads, , spinning more expensive. case web server can tied many threads waiting blocking operations complete, new requests have wait new thread, meaning have wait else's blocking operation. async, thread waiting on blocking operation can returned pool can service other (possibly cpu-bound) requests.

read this: http://msdn.microsoft.com/en-us/library/ee728598(vs.100).aspx

...and read this: http://blog.stephencleary.com/2013/11/there-is-no-thread.html

i understand thread grabbed pool 1 time blocking operation done, don't know thread executes blocking operation itself.

no thread executes blocking operation. cpu waiting on device -- network card, or disk controller, homecoming output.

threads cpu-bound artifacts, ram, since operates on buss according cpu clock rate. there other devices in machine usb, network card, disks, etc. these other devices i/o bound because input/output devices.

asp.net-mvc multithreading asynchronous threadpool

Comments

Post a Comment

Popular posts from this blog

Delphi change the assembly code of a running process -

Delphi change the assembly code of a running process - i'm trying alter address 00741fa5 has push test.009e721c . alter push test.009e71c8 . procedure callback; asm force $9e71c8 end; procedure tform2.btn1click(sender: tobject); var ppid :dword; pprocess : cardinal; begin getwindowthreadprocessid(findwindow(nil,pchar('test')), @ppid); pprocess := openprocess(process_all_access, false, ppid); injectasm(pprocess, $741fa5, 10, integer(@callback), 0); end; here injectasm function (with error checking) function injectasm(process: longword; injectaddress, injectsize, codeaddress, codesize : integer): pointer; var csize, rsize : integer; replaced : array of byte; jmp : array [0..4] of byte; jmpaddress : integer; nopv : byte; : integer; nbr: ulong_ptr; begin //injectsize must equal or greater 5, because need space our //(far) jmp wwxxyyzz instruction //if there's no space, inject in place of few instructions if injectsize ...
Read more

json - Hibernate and Jackson (java.lang.IllegalStateException: Cannot call sendError() after the response has been committed) -

json - Hibernate and Jackson (java.lang.IllegalStateException: Cannot call sendError() after the response has been committed) - hello have problem hibernate , jackson. have 2 pojos @entity @table(name = "users") public class user implements serializable { static final long serialversionuid = 4235637833262722256l; @id @generatedvalue private int id; @column(name = "creation_date") private date creationdate; @column(name = "first_name") private string firstname; @column(name = "last_name") private string lastname; @version @column(name = "version") private int version; @column(name = "e_mail") private string email; @column(name = "enabled") private boolean enabled; @column(name = "login") private string login; @column(name = "password") private string password; @jsonmanagedreference("role") @onetomany(mappedby = "user", cascade = cascadetype.all,fetch = fetchtyp...
Read more

C++ 11 "class" keyword -

C++ 11 "class" keyword - i've started using c++ 11 little bit more , have few questions on special uses of class keyword. know it's used declare class, there's 2 instances have seen don't understand: method<class t>(); and class class_name *var; why precede typename keyword class in first example, , keyword pointer in sec example? that known elaborated type specifier , necessary when class name "shadowed" or "hidden" , need explicit. class t { }; // love of god don't t t; t t2; if compiler smart, give these warnings: main.cpp:15:5: error: must utilize 'class' tag refer type 't' in scope t t2; ^ class main.cpp:14:7: note: class 't' hidden non-type declaration of 't' here t t; ^ if class not defined, deed forwards declaration. for example: template <typename t> void method() { using type = typename t::value_type; } method...
Read more