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Message Queues (2.4 vs. 2.6)

I am seeing a dramatic difference between 2.4.26 and 2.6.10 in how
fast messages are transferred to a log file using a message queue,
i.e., using msgsnd & msgrcv.  On 2.4.26, the messages appear in the
log file in at most a few seconds.  On 2.6.10, it may take 20 to 30
seconds before the messages appear in the log file.  Since the log
file is there primarily to help debug crashes, very little useful
information is there with this large delay.  I am using a powerpc
processor.

Has anyone else seen this sort of behavior in 2.4 vs. 2.6 and are
there any suggestions on how to fix it?
0
Bill
5/17/2008 1:38:10 AM
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"Bill" <jobhunts02@aol.com> wrote in message 
news:c6ffac56-f659-46d2-b06b-bf0333c4308a@t54g2000hsg.googlegroups.com...
>I am seeing a dramatic difference between 2.4.26 and 2.6.10 in how
> fast messages are transferred to a log file using a message queue,
> i.e., using msgsnd & msgrcv.  On 2.4.26, the messages appear in the
> log file in at most a few seconds.  On 2.6.10, it may take 20 to 30
> seconds before the messages appear in the log file.  Since the log
> file is there primarily to help debug crashes, very little useful
> information is there with this large delay.  I am using a powerpc
> processor.
>
> Has anyone else seen this sort of behavior in 2.4 vs. 2.6 and are
> there any suggestions on how to fix it?

Maybe it is obvious to everybody else, but I have not idea what you are 
referring to.  2.4 of what?

-- 
Regards,
Richard.

+ http://www.FreeRTOS.org & http://www.FreeRTOS.org/shop
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0
noemail2969 (253)
5/17/2008 8:27:10 AM
FreeRTOS.org wrote:
> "Bill" <jobhunts02@aol.com> wrote in message 
> news:c6ffac56-f659-46d2-b06b-bf0333c4308a@t54g2000hsg.googlegroups.com...
>> I am seeing a dramatic difference between 2.4.26 and 2.6.10 in how
>> fast messages are transferred to a log file using a message queue,
>> i.e., using msgsnd & msgrcv.  On 2.4.26, the messages appear in the
>> log file in at most a few seconds.  On 2.6.10, it may take 20 to 30
>> seconds before the messages appear in the log file.  Since the log
>> file is there primarily to help debug crashes, very little useful
>> information is there with this large delay.  I am using a powerpc
>> processor.
>>
>> Has anyone else seen this sort of behavior in 2.4 vs. 2.6 and are
>> there any suggestions on how to fix it?
> 
> Maybe it is obvious to everybody else, but I have not idea what you are 
> referring to.  2.4 of what?

Linux kernel version, I assume.

0
Arlet
5/17/2008 8:29:08 AM
Bill wrote:

> I am seeing a dramatic difference between 2.4.26 and 2.6.10 in how
> fast messages are transferred to a log file using a message queue,
> i.e., using msgsnd & msgrcv.  On 2.4.26, the messages appear in the
> log file in at most a few seconds.  On 2.6.10, it may take 20 to 30
> seconds before the messages appear in the log file.  Since the log
> file is there primarily to help debug crashes, very little useful
> information is there with this large delay.  I am using a powerpc
> processor.
> 
> Has anyone else seen this sort of behavior in 2.4 vs. 2.6 and are
> there any suggestions on how to fix it?

I can't believe that it's intrinsic to 2.6 .  We're using an up-to-date
Debian 4 release, and getting response times in very small fractions of a
second using msgsnd/msgrcv.  It's a music playing app, and even a delay
like 1/4 second would be intolerable.  We've paid no great attention to
setting up the message queue -- just used nice to give priority to our
critical processes.

        Mel.

0
Mel
5/17/2008 11:11:05 AM
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