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From: Ben Greear <greearb@candelatech.com>
To: george anzinger <george@mvista.com>
Cc: Horst von Brand <vonbrand@sleipnir.valparaiso.cl>,
	linux-kernel@vger.kernel.org,
	high-res-timers-discourse@lists.sourceforge.net
Subject: Re: No 100 HZ timer!
Date: Sun, 15 Apr 2001 19:41:40 -0700	[thread overview]
Message-ID: <3ADA5BE4.367741CA@candelatech.com> (raw)
In-Reply-To: <200104131205.f3DC5KV11393@sleipnir.valparaiso.cl> <3AD77540.42BF138E@mvista.com>

george anzinger wrote:
> 
> Horst von Brand wrote:
> >
> > Ben Greear <greearb@candelatech.com> said:
> >
> > [...]
> >
> > > Wouldn't a heap be a good data structure for a list of timers?  Insertion
> > > is log(n) and finding the one with the least time is O(1), ie pop off the
> > > front....  It can be implemented in an array which should help cache
> > > coherency and all those other things they talked about in school :)
> >
> > Insertion and deleting the first are both O(log N). Plus the array is fixed
> > size (bad idea) and the jumping around in the array thrashes the caches.

Jumping around an array can't be much worse than jumping around
a linked list, can it?

It does not have to be fixed length, though it wouldn't be log(n) to
grow the array, it can still be done...and once you reach maximal
size, you won't be growing it any more...

I had forgotten about the log(n) to delete, though log(n) is
still pretty good.  As others have suggested, it might be good
to have a linked list for very-soon-to-expire timers.  However,
they would have to be few enough that your linear insert was
not worse than a log(n) instert and a log(n) delete...

> > --
> And your solution is?


> 
> George

-- 
Ben Greear (greearb@candelatech.com)  http://www.candelatech.com
Author of ScryMUD:  scry.wanfear.com 4444        (Released under GPL)
http://scry.wanfear.com               http://scry.wanfear.com/~greear

  parent reply	other threads:[~2001-04-16  2:15 UTC|newest]

Thread overview: 118+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-04-11 17:56 No 100 HZ timer! Bret Indrelee
2001-04-12 17:39 ` george anzinger
2001-04-12 21:19   ` Bret Indrelee
2001-04-12 22:20     ` george anzinger
2001-04-13  4:00       ` Bret Indrelee
2001-04-13  6:32         ` Ben Greear
2001-04-13  8:42           ` george anzinger
2001-04-13 10:36             ` Jamie Lokier
2001-04-13 16:07               ` george anzinger
2001-04-13 23:00                 ` Jamie Lokier
2001-04-13 12:05           ` Horst von Brand
2001-04-13 21:53             ` george anzinger
2001-04-13 23:10               ` Jamie Lokier
2001-04-16  3:02                 ` Ben Greear
2001-04-16  2:46                   ` Jamie Lokier
2001-04-16 12:36                     ` Mark Salisbury
2001-04-16 19:19                       ` george anzinger
2001-04-16 20:45                         ` Albert D. Cahalan
2001-04-16 21:29                           ` Chris Wedgwood
2001-04-16 22:25                           ` george anzinger
2001-04-16 23:57                         ` Mark Salisbury
2001-04-17  0:45                           ` george anzinger
2001-04-17 12:12                             ` Mark Salisbury
2001-04-17 12:51                         ` Mark Salisbury
2001-04-17 18:53                           ` george anzinger
2001-04-17 19:41                             ` Jamie Lokier
2001-04-23  8:05                             ` Ulrich Windl
2001-04-23 13:22                               ` Mark Salisbury
2001-04-16  2:41               ` Ben Greear [this message]
  -- strict thread matches above, loose matches on Subject: below --
2001-08-01 17:22 No 100 HZ timer ! george anzinger
2001-08-01 19:34 ` Chris Friesen
2001-08-01 19:49   ` Richard B. Johnson
2001-08-01 20:08     ` Mark Salisbury
2001-08-01 20:33     ` george anzinger
2001-08-01 21:20   ` george anzinger
2001-08-02  4:28     ` Rik van Riel
2001-08-02  6:03       ` george anzinger
2001-08-02 14:39         ` Oliver Xymoron
2001-08-02 16:36           ` george anzinger
2001-08-02 17:05             ` Oliver Xymoron
2001-08-02 17:46               ` george anzinger
2001-08-02 18:41                 ` Oliver Xymoron
2001-08-02 21:18                   ` george anzinger
2001-08-02 22:09                     ` Oliver Xymoron
2001-08-02 17:26             ` John Alvord
2001-04-12 13:14 No 100 HZ timer! Bret Indrelee
2001-04-12 12:58 No 100 HZ timer ! Mark Salisbury
2001-04-11  9:06 schwidefsky
2001-04-10 14:42 schwidefsky
2001-04-10 12:54 schwidefsky
2001-04-10 11:38 schwidefsky
2001-04-10 11:54 ` Alan Cox
2001-04-10  7:29 schwidefsky
2001-04-10  7:27 schwidefsky
2001-04-09 15:54 schwidefsky
2001-04-09 18:30 ` Jeff Dike
2001-04-09 18:19   ` Mark Salisbury
2001-04-09 20:12     ` Alan Cox
2001-04-09 20:32       ` Mark Salisbury
2001-04-09 22:31       ` Mikulas Patocka
2001-04-09 22:35         ` Alan Cox
2001-04-10 11:43           ` David Schleef
2001-04-10 12:04             ` Mikulas Patocka
2001-04-10 12:31               ` David Schleef
2001-04-10 12:34                 ` Mark Salisbury
2001-04-10 14:10                 ` Mikulas Patocka
2001-04-10 13:35                   ` root
2001-04-10 14:22                   ` Andi Kleen
2001-04-10 15:43                   ` Alan Cox
2001-04-12  5:25                     ` watermodem
2001-04-12  8:45                       ` Jamie Lokier
2001-04-10 17:15                   ` Jamie Lokier
2001-04-10 17:27                     ` Alan Cox
2001-04-10 17:35                       ` Jamie Lokier
2001-04-10 18:17                         ` Alan Cox
2001-04-10 18:24                           ` Jamie Lokier
2001-04-10 19:28                             ` george anzinger
2001-04-10 20:02                               ` mark salisbury
2001-04-10 22:08                                 ` george anzinger
2001-04-11  0:48                                   ` Mark Salisbury
2001-04-11  2:35                                     ` george anzinger
2001-04-12  0:24                                       ` Mark Salisbury
2001-04-11 16:11                                     ` Jamie Lokier
2001-04-11 16:59                                       ` george anzinger
2001-04-11 18:57                                         ` Jamie Lokier
2001-04-11 19:21                                           ` John Alvord
2001-04-12  8:41                                             ` Jamie Lokier
2001-08-01  1:08                               ` george anzinger
2001-08-11 11:57                                 ` Pavel Machek
2001-08-14 15:59                                   ` Jamie Lokier
2001-08-14 16:57                                     ` george anzinger
2001-04-10 19:50                             ` Zdenek Kabelac
2001-04-11 11:42                               ` Maciej W. Rozycki
2001-04-11 16:13                                 ` Jamie Lokier
2001-04-12  9:51                                   ` Maciej W. Rozycki
2001-04-10 19:42                       ` Zdenek Kabelac
2001-04-10 12:19             ` Mark Salisbury
2001-04-10 17:51             ` yodaiken
2001-04-11 18:43           ` Oliver Xymoron
2001-04-10 12:11       ` Mark Salisbury
2001-04-10  5:51     ` Andi Kleen
2001-04-10  9:33       ` Martin Mares
2001-04-10 10:00         ` Albert D. Cahalan
2001-04-10 12:14         ` Mark Salisbury
2001-04-11  5:55           ` Karim Yaghmour
2001-04-10 11:18       ` Alan Cox
2001-04-10 12:02         ` Andi Kleen
2001-04-10 12:12           ` Alan Cox
2001-04-10 12:27             ` Mark Salisbury
2001-04-10 12:32             ` Andi Kleen
2001-04-10 12:36               ` Alan Cox
2001-04-10 12:37                 ` Andi Kleen
2001-04-10 18:45               ` Stephen D. Williams
2001-04-10 19:59                 ` Andi Kleen
2001-04-10 12:07       ` Mark Salisbury
2001-04-10 12:45         ` Andi Kleen
2001-04-10 12:42           ` Mark Salisbury
2001-04-10 12:54             ` Andi Kleen

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