linux-kernel - Re: [PATCH] printk timestamp post-boot suppression

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <48B5723C.4020705@onelan.com>
Date:	Wed, 27 Aug 2008 16:26:52 +0100
From:	Simon Farnsworth <simon.farnsworth@...lan.com>
To:	Joe Korty <joe.korty@...r.com>
CC:	Ingo Molnar <mingo@...e.hu>,
	Linux Kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] printk timestamp post-boot suppression

Joe Korty wrote:
> Suppress printk timestamping after system boot.
> 
> The timestamp printk prefix seems most useful during boot,
> where it easily shows where the boot sequence is spending
> its time.
> 
It's also very useful while the system is running. We've had problems
with systems where the HDD or libata was "hiccuping" and stalling the
entire system for 30 seconds; our logs were useless, as syslog was
timestamping with the timestamp *after* the stall ended (as that was
when it received the message), and dmesg had no timestamps.

In this case, our problem ran away and hid when we turned on printk
timestamps, but if it recurred, we'd want the timestamps available to
let us work out which operation was taking lots of time, without having
to rebuild the kernel.
-- 
Simon Farnsworth

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