2001-04-19 15:10:13

by Praveen Rajendran

[permalink] [raw]
Subject: linux timer performance ?

hi

I am working on a kernel module which requires the addition of a large
number of kernel timers to expire statistical values ( including time
) maintained in a table.

One alternative would be to use a single timer and traverse the entire
table and use the existing system time to expire the values ( comparing
it with the time already stored in the table )when the timer expires .

Following the method I describe first I would have to add a large number
of timers ( around 2000) ... would this cause any significant
performance drop ? which method should I use ?

thanks in advance

Praveen





2001-04-19 16:19:51

by Jeremy Jackson

[permalink] [raw]
Subject: Re: linux timer performance ?

Praveen Rajendran wrote:

> hi
>
> I am working on a kernel module which requires the addition of a large
> number of kernel timers to expire statistical values ( including time
> ) maintained in a table.
>
> One alternative would be to use a single timer and traverse the entire
> table and use the existing system time to expire the values ( comparing
> it with the time already stored in the table )when the timer expires .

Most versions of cron claim to be very scalable, and use an optimized
algorithm to do the second option. (avoiding linear scan) You could likely
just cut and paste
the code. Problem solved?

>
>
> Following the method I describe first I would have to add a large number
> of timers ( around 2000) ... would this cause any significant
> performance drop ? which method should I use ?
>
> thanks in advance
>
> Praveen
>
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