Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.databases.ms-sqlserver > #1998 > unrolled thread

Alternative to WAITFOR DELAY

Back to article view | Back to comp.databases.ms-sqlserver

Contents

  Alternative to WAITFOR DELAY Anton Shepelev <anton.txt@gmail.com> - 2017-11-29 23:38 +0300
    Re: Alternative to WAITFOR DELAY Erland Sommarskog <esquel@sommarskog.se> - 2017-11-29 22:49 +0100
      Re: Alternative to WAITFOR DELAY Anton Shepelev <anton.txt@g{oogle}mail.com> - 2017-11-30 13:58 +0300

#1998 — Alternative to WAITFOR DELAY

Hello, all

Is there a more granular way to ease a tight polling
loop in T-SQL than WAITFOR DEALAY?  A delay of  3.33
milliseconds being a tad too long for my purposes, I
seek a way to implement delays of about half a  mil-
lisecond or shorter.  I do not need the precision of
real-time systems and will accept  any  solution  to
prevent a fast WHILE 1=1 loop from hogging the CPU.

-- 
()  ascii ribbon campaign -- against html e-mail
/\  http://preview.tinyurl.com/qcy6mjc [archived]

[toc] | [next] | [standalone]

#1999

Anton Shepelev (anton.txt@gmail.com) writes:
> Is there a more granular way to ease a tight polling
> loop in T-SQL than WAITFOR DEALAY?  A delay of  3.33
> milliseconds being a tad too long for my purposes, I
> seek a way to implement delays of about half a  mil-
> lisecond or shorter.  I do not need the precision of
> real-time systems and will accept  any  solution  to
> prevent a fast WHILE 1=1 loop from hogging the CPU.
> 

I guess that you could write a CLR procedure for the task.

[toc] | [prev] | [next] | [standalone]

#2000

Erland Sommarskog to Anton Shepelev:

>>Is  there  a  more  granular  way  to ease a tight
>>polling loop in T-SQL than WAITFOR DEALAY?  A  de-
>>lay of  3.33 milliseconds being a tad too long for
>>my purposes, I seek a way to implement  delays  of
>>about  half  a   millisecond or shorter.  I do not
>>need the precision of real-time systems  and  will
>>accept  any  solution  to prevent a fast WHILE 1=1
>>loop from hogging the CPU.
>
>I guess that you could write a  CLR  procedure  for
>the task.

Thanks.   No idea why it didn't occur to me.  I have
written .NET assemblies for MSSQL before.   If  per-
formace  testing  shows a need for a shorter delay I
will definitely follow your advice.

Meanwhile, my loop switches to zero  delay  once  it
finds  work  to  do, and back to a 3.3 ms delay once
all work is done and in incoming queue is empty.

-- 
()  ascii ribbon campaign - against html e-mail
/\  http://preview.tinyurl.com/qcy6mjc [archived]

[toc] | [prev] | [standalone]

Back to top | Article view | comp.databases.ms-sqlserver

csiph-web