#14345 – very long pause with clocksource=tsc after checking the root fs

Bug 14345 - very long pause with clocksource=tsc after checking the root fs

Summary: very long pause with clocksource=tsc after checking the root fs

Status:	CLOSED WORKSFORME

Alias:	None

Product:	Sisyphus
Classification:	Development
Component:	SysVinit (show other bugs)
Version:	unstable
Hardware:	all Linux

Importance:	P2 minor
Assignee:	Dmitry V. Levin
QA Contact:	qa-sisyphus

URL:
Keywords:

Depends on:
Blocks:

Reported:	2008-02-06 18:55 MSK by Ivan Zakharyaschev
Modified:	2026-09-10 08:06 MSK (History)
CC List:	1 user (show)

See Also:

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Description

Ivan Zakharyaschev 2008-02-06 18:55:35 MSK

SysVinit-2.86-alt1

I discovered this while experimenting because of the bug with system clock
https://bugzilla.altlinux.org/show_bug.cgi?id=14258 . 

The described effect appears together with a similar effect:
https://bugzilla.altlinux.org/show_bug.cgi?id=14343 .

$ rpm -q kernel-image-wks-smp-2.6.18-alt1 -i
Name        : kernel-image-wks-smp         Relocations: (not relocateable)
Version     : 2.6.18                            Vendor: ALT Linux Team
Release     : alt1                          Build Date: Срд 13 Дек 2006 02:28:15
Install date: Срд 21 Фев 2007 02:43:51      Build Host: bee5.hasher.altlinux.org
Group       : System/Kernel and hardware    Source RPM:
kernel-image-wks-smp-2.6.18-alt1.src.rpm
Size        : 44948311                         License: GPL
Packager    : Konstantin A. Lepikhov <lakostis@altlinux.ru>
<....>
Steps to Reproduce:
1. boot 2.6.24-wks-smp-alt1 with clocksource=tsc
2.
3.
Actual Results:  
After the root fs is mounted read-only (and it is written that it has been
checked), the boot-up sequence pauses for about 40 sec. Only after that the
message like "Remounting the root filesystem read-write" is written.

Expected Results:  
Normally, there is no pause at all at this moment (e.g., on 2.6.24-wks-smp-alt1
with default options).

Comment 1

Ivan Zakharyaschev 2008-02-06 19:33:01 MSK

(In reply to comment #0)
> After the root fs is mounted read-only (and it is written that it has been
> checked),

I meant after it was checked while being read-only; before remounting it in
read-write mode.

Comment 2

Ivan Zakharyaschev 2008-02-07 05:07:02 MSK

I also experienced this delay on 2.6.24-std-def-alt2 with clocksource=tsc.

(With this option, 2.6.24-std-def-alt2 also has the bad behavior of the system
clock: https://bugzilla.altlinux.org/show_bug.cgi?id=14258#c18 ).


Perhaps, this is not a bug and an expected behavior under this kernel parameter.
But I wonder why other programs work without delays then.

Comment 3

Michael Shigorin 2010-08-25 08:48:10 MSD

Ivan, is it still there?

Comment 4

Anton Farygin 2026-09-10 08:06:24 MSK

Репорт о 40-секундной паузе при загрузке с clocksource=tsc на ядрах 2.6.24 и SysVinit 2.86 (2008). Ни того ядра, ни того пакета давно нет: в Сизифе sysvinit 3.00-alt2 и ядра 6.12/6.18, а выбор источника времени и калибровка TSC в ядре с тех пор переписаны полностью. Воспроизвести не на чем.

WORKSFORME; если что-то похожее встретится на актуальном ядре — заведите новый баг с dmesg.