c++ - Does a worker thread need to sleep? -



c++ - Does a worker thread need to sleep? -

a normal worker thread runs in loop in checks available tasks in queue , consumes them. i've seem examples thread waits couple of milliseconds when there no available task, using std::this_thread::sleep_for() example. however, want thread consume tasks minimal latency, don't utilize sleep. bad? should worker thread sleep milliseconds when checking tasks?

if "roll own" queue or message system, 1 way avoid consuming 100% cpu "sleep" bit when there's no work available. however, having other mechanism lets os take care of (semaphore(s), os-based queue such pipe or mailbox system, or using network message passing mechanism, etc) much better, since simplifies application, , allows os take care of sleeping/waking processing.

of course, depends on trying accomplish , expectation - if code intended run on, say, mobile phone, not wasting cpu-cycles critical, because kills battery life wasting cpu cycles used on other task. on other hand, if messaging scheme in abs brakes of car, , require measure time of pulses sensor sub-microsecond accuracy, sleeping bad idea, since code sleep lot longer 1 time pulse abs sensor.

if it's in desktop, nobody care if application doesn't sleep if runs few seconds or min or more. if keeps using 1 core @ 100% hours (and app isn't producing @ to the lowest degree valuable cycles wasted - calculating next largest prime number in world or folding proteins worth wasting cycles on. saving 0.5 milliseconds on receiving packet net isn't).

only (and other people involved in project of course) know design criteria project. not can "ask internet" about. above should give guidance 1 time have figured out design criteria is, however.

c++ multithreading sleep thread-sleep worker-thread

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