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From: ori@eigenstate.org
To: 9fans@9fans.net
Subject: Re: [9fans] Problem with outputing from kernel
Date: Wed, 04 Oct 2023 11:23:32 -0400	[thread overview]
Message-ID: <8F4E7F800F7C886A9633672C3DC68E95@eigenstate.org> (raw)
In-Reply-To: <16964183030.24ffCe99.58412@composer.9fans.topicbox.com>

Quoth dusan3sic@gmail.com:
> I added some logs in /sys/src/9/port/proc.c for some tests of the scheduler, I want to see at what moments do real time processes take the cpu. I did that with simple prints with the intention of doing cat /dev/kmesg > someFile because all the prints are stored there.  
> 
> The problem is that the flow of output just randomly stops at times and continues(only once by test) and i lose some of the output  which is really important. Any ideas why?

are you printing from an interrupt context? use iprint for that.

also, are you looking for trace(1)? we ship with a tool for showing
scheduler decisions.

> 
> Also I was doing with tail -f /dev/kmesg in the background and without that /dev/kmesg loses the start of output up to some random moment where it shows it. Could the problem be that i have too many outputs?

that's what tail *does*. It shows the tail (by default, last 10 lines) of the file.


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  reply	other threads:[~2023-10-04 15:23 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-04 11:18 dusan3sic
2023-10-04 15:23 ` ori [this message]
2023-10-04 16:56 ` Kurt H Maier via 9fans
2023-10-09 18:37   ` dusan3sic

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