lkml.org 
[lkml]   [2002]   [Feb]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Short question regarding generic_make_request()

On Mon, 4 Feb 2002, Steffen Persvold wrote:

> [root@damd1 root]# ping sci4
> PING sci4 (192.168.4.4) from 192.168.4.3 : 56(84) bytes of data.
> 64 bytes from sci4 (192.168.4.4): icmp_seq=0 ttl=255 time=238 usec

> For simplicity I'll say ~200usec. When I change the receive handler
> from a tasklet to a kernel thread, the numbers look like this :
>
> [root@damd1 root]# ping sci4
> PING sci4 (192.168.4.4) from 192.168.4.3 : 56(84) bytes of data.
> 64 bytes from sci4 (192.168.4.4): icmp_seq=0 ttl=255 time=4.215 msec
> 64 bytes from sci4 (192.168.4.4): icmp_seq=1 ttl=255 time=5.728 msec

this shows some sort of wakeup or softirq handling irregularity. A number
of softirq latency bugs were fixed, i'd suggest to try this with any
recent kernel (or recent errata kernel rpms).

Ingo

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:23    [W:0.060 / U:0.200 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site