EXT3 - freeze ups during disk writes

EXT3 - freeze ups during disk writes

[Erik Elmore]

Ever since I started using ext3fs, whenever there is a disk write, the 
kernel sucks up all of the CPU thereby preempting everything and causing 
the PC to freeze momentarily.  Could this possibly be caused by the 
journaling code in ext3?

-Erik

Re: EXT3 - freeze ups during disk writes

[Mike Fedyk]

On Sat, Dec 01, 2001 at 12:47:19AM -0600, Erik Elmore wrote:
> Ever since I started using ext3fs, whenever there is a disk write, the 
> kernel sucks up all of the CPU thereby preempting everything and causing 
> the PC to freeze momentarily.  Could this possibly be caused by the 
> journaling code in ext3?
> 

You really need to give kernel version, gcc version and what things were
happening at the time.

I can think of five different things that this general description has
brought up.

mf

Re: EXT3 - freeze ups during disk writes

[Erik Elmore]

ahhhh... woops... every official kernel since ext3 made it into the 
official tree, 2.4.14 if memory serves.  I'm using gcc 2.95.3.  And to 
clarify the bug, say on a large disk write, the pause isn't constant, 
it just pauses for a second every few seconds during the write.  For 
smaller writes, it will pause only once, I assume while performing the 
actual write to disk.

Erik


On Fri, 30 Nov 2001, Mike Fedyk wrote:

> On Sat, Dec 01, 2001 at 12:47:19AM -0600, Erik Elmore wrote:
> > Ever since I started using ext3fs, whenever there is a disk write, the 
> > kernel sucks up all of the CPU thereby preempting everything and causing 
> > the PC to freeze momentarily.  Could this possibly be caused by the 
> > journaling code in ext3?
> > 
> 
> You really need to give kernel version, gcc version and what things were
> happening at the time.
> 
> I can think of five different things that this general description has
> brought up.
> 
> mf
> 

Re: EXT3 - freeze ups during disk writes

[Andrew Morton]

Erik Elmore wrote:
> 
> ahhhh... woops... every official kernel since ext3 made it into the
> official tree, 2.4.14 if memory serves.  I'm using gcc 2.95.3.  And to
> clarify the bug, say on a large disk write, the pause isn't constant,
> it just pauses for a second every few seconds during the write.  For
> smaller writes, it will pause only once, I assume while performing the
> actual write to disk.
> 

I've seen a couple of reports where ext3 appears to exacerbate
the effects of poor hdparm settings.  What is your raw disk
throughput, from `hdparm -t /dev/hda'?

Re: EXT3 - freeze ups during disk writes

[Erik Elmore]

> I've seen a couple of reports where ext3 appears to exacerbate
> the effects of poor hdparm settings.  What is your raw disk
> throughput, from `hdparm -t /dev/hda'?

`hdparm -t /dev/hda` reports:

# hdparm -t /dev/hda

/dev/hda:
 Timing buffered disk reads:  64 MB in 16.76 seconds =  3.82 MB/sec


Erik

Re: EXT3 - freeze ups during disk writes

[Mark Hahn]

in other mail I asked Erik about the disk's mode: it is PIO,
so the pathetic speed and crippling VM/Ext2 performance is 
entirely expected.  I'm guessing he's missing CONFIGs of either
the chipset-specific driver or one of:
CONFIG_BLK_DEV_IDEDMA_PCI=y
CONFIG_BLK_DEV_ADMA=y
CONFIG_IDEDMA_PCI_AUTO=y
CONFIG_BLK_DEV_IDEDMA=y
CONFIG_IDEDMA_AUTO=y


> > I've seen a couple of reports where ext3 appears to exacerbate
> > the effects of poor hdparm settings.  What is your raw disk
> > throughput, from `hdparm -t /dev/hda'?
> 
> `hdparm -t /dev/hda` reports:
> 
> # hdparm -t /dev/hda
> 
> /dev/hda:
>  Timing buffered disk reads:  64 MB in 16.76 seconds =  3.82 MB/sec

Re: EXT3 - freeze ups during disk writes

[Ivanovich]

A Diumenge 02 Desembre 2001 19:15, Mark Hahn va escriure:
> in other mail I asked Erik about the disk's mode: it is PIO,
> so the pathetic speed and crippling VM/Ext2 performance is
> entirely expected.  I'm guessing he's missing CONFIGs of either
> the chipset-specific driver or one of:
> CONFIG_BLK_DEV_IDEDMA_PCI=y
> CONFIG_BLK_DEV_ADMA=y
> CONFIG_IDEDMA_PCI_AUTO=y
> CONFIG_BLK_DEV_IDEDMA=y
> CONFIG_IDEDMA_AUTO=y
>
> > > I've seen a couple of reports where ext3 appears to exacerbate
> > > the effects of poor hdparm settings.  What is your raw disk
> > > throughput, from `hdparm -t /dev/hda'?
> >
> > `hdparm -t /dev/hda` reports:
> >
> > # hdparm -t /dev/hda
> >
> > /dev/hda:
> >  Timing buffered disk reads:  64 MB in 16.76 seconds =  3.82 MB/sec

maybe the only thing he is missing is the *AUTO configs

you could try:
# /sbin/hdparm -c 1 -d 1 /dev/hda
which tries to do this:
/dev/hda:
 setting 32-bit I/O support flag to 1
 setting using_dma to 1 (on)

and then test again with -t to see if it gets better...

Re: EXT3 - freeze ups during disk writes

[Erik Elmore]

heh, that makes sense, if I want my hardware to work right, then I need to 
build the damn driver.  I added in the support and tweaked my startup 
scripts and not only did that pause go away, my throughput has improved as 
well.  Thanks guys.

Erik

Re: EXT3 - freeze ups during disk writes

[Bernd Eckenfels]

In article <Pine.LNX.4.33.0112011209190.3893-100000@localhost.localdomain> you wrote:
> And to 
> clarify the bug, say on a large disk write, the pause isn't constant,

You should elaborate more on the type of disks writes. Is this a write to a
single large file, a rename/delte of a large tree, ot generating of a lot of
files. Cause there is a difference in the meta data and data handling. both
where known to take too much time in different versions.

Greetings
Bernd

Re: EXT3 - freeze ups during disk writes

[Erik Elmore]

> You should elaborate more on the type of disks writes. Is this a write to a
> single large file, a rename/delte of a large tree, ot generating of a lot of
> files. Cause there is a difference in the meta data and data handling. both
> where known to take too much time in different versions.

It appears when writing a single large file such as downloading or copying 
a file, and also when I copy a large number of smaller files at once.  I 
have noticed no performance hits when renaming or deleting a large number 
of files at once.

Erik

Re: EXT3 - freeze ups during disk writes

[Jan-Hendrik Palic]

[-- Attachment #1: Type: text/plain, Size: 1722 bytes --]

Hi .. 

I have to say, I had it too .. on my IBook2 

On Sun, Dec 02, 2001 at 02:55:04PM +0100, Bernd Eckenfels wrote:
>In article <Pine.LNX.4.33.0112011209190.3893-100000@localhost.localdomain> you wrote:
>> And to 
>> clarify the bug, say on a large disk write, the pause isn't constant,
>You should elaborate more on the type of disks writes. Is this a write to a
>single large file, a rename/delte of a large tree, ot generating of a lot of
>files. Cause there is a difference in the meta data and data handling. both
>where known to take too much time in different versions.

at me .. 

I kompiled a Ben0 Kernel with ext3 support and then I made tune2fs to
convert ext2 to ext3 partitions by making a .journal - file! 

After 45 min after the reboot the ext3 system, the IBook freezes at havy
disk/IO (an untar at OpenOffice source , tar.gz 100MB, Sourcetree
550MB).

The IBook freezed and I reseted it .. but I had to install the whole
system .. the yaboot wasn't able to find a kernel on the / Partition.
(ext3 too) :)

			Regards


				Jan
>Greetings
>Bernd
>-
>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/
>

-- 
One time, you all will be emulated by linux!

----
Jan- Hendrik Palic
Url:"http://www.billgotchy.de"
E-Mail: "palic@billgotchy.de"

-----BEGIN GEEK CODE BLOCK-----
Version: 3.12
GCS d- s: a-- C++ UL++ P+++ L+++ E W++ N+ o+ K- w--- 
O- M- V- PS++ PE Y+ PGP++ t--- 5- X+++ R-- tv- b++ DI-- D+++ 
G+++ e+++ h+ r++ z+ 
------END GEEK CODE BLOCK------

[-- Attachment #2: Type: application/pgp-signature, Size: 232 bytes --]

Re: EXT3 - freeze ups during disk writes

[Andrew Morton]

Jan-Hendrik Palic wrote:
> 
> The IBook freezed and I reseted it .. but I had to install the whole
> system .. the yaboot wasn't able to find a kernel on the / Partition.
> (ext3 too) :)
> 

An unrecovered ext3 filesystem is probably unrecognisable to
yaboot.  I'm told that yaboot 1.3.5 and later have changes which
permit booting from unrecovered ext3 filesystems.

Re: EXT3 - freeze ups during disk writes

[Jan-Hendrik Palic]

[-- Attachment #1: Type: text/plain, Size: 1193 bytes --]

Hi ... 

On Mon, Dec 03, 2001 at 04:17:44PM -0800, Andrew Morton wrote:
>> The IBook freezed and I reseted it .. but I had to install the whole
>> system .. the yaboot wasn't able to find a kernel on the / Partition.
>> (ext3 too) :)
>An unrecovered ext3 filesystem is probably unrecognisable to
>yaboot.  I'm told that yaboot 1.3.5 and later have changes which
>permit booting from unrecovered ext3 filesystems.

hmmm ok ... thnx ... :)

But the IBook freezed with the 2.4.15-ben0 on haevy harddisk/IO .... 

what could it be?

	Best regards!

			Jan

>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/
>

-- 
One time, you all will be emulated by linux!

----
Jan- Hendrik Palic
Url:"http://www.billgotchy.de"
E-Mail: "palic@billgotchy.de"

-----BEGIN GEEK CODE BLOCK-----
Version: 3.12
GCS d- s: a-- C++ UL++ P+++ L+++ E W++ N+ o+ K- w--- 
O- M- V- PS++ PE Y+ PGP++ t--- 5- X+++ R-- tv- b++ DI-- D+++ 
G+++ e+++ h+ r++ z+ 
------END GEEK CODE BLOCK------

[-- Attachment #2: Type: application/pgp-signature, Size: 232 bytes --]

Re: EXT3 - freeze ups during disk writes

[Mike Fedyk]

On Tue, Dec 04, 2001 at 10:53:19PM +0100, Jan-Hendrik Palic wrote:
> Hi ... 
> 
> On Mon, Dec 03, 2001 at 04:17:44PM -0800, Andrew Morton wrote:
> >> The IBook freezed and I reseted it .. but I had to install the whole
> >> system .. the yaboot wasn't able to find a kernel on the / Partition.
> >> (ext3 too) :)
> >An unrecovered ext3 filesystem is probably unrecognisable to
> >yaboot.  I'm told that yaboot 1.3.5 and later have changes which
> >permit booting from unrecovered ext3 filesystems.
> 
> hmmm ok ... thnx ... :)
> 
> But the IBook freezed with the 2.4.15-ben0 on haevy harddisk/IO .... 
> 
> what could it be?
> 

I would suggest you try another ben0, or use a kernel available from the bk
repositories.

Check out www.penguinppc.org/

mf

Re: EXT3 - freeze ups during disk writes

[Stephane Chauveau]

Hi,

this is a reply for the thread started by Erik Elmore on Dec 02 2001.

I experienced the same problem today after switching from a customized
kernel (2.4.17) to the official debian kernel (2.4.18). During intensive
ext3 disk writes, the PC freezes each 4 or 5 seconds.

The generic debian kernel does not enable dma by default. I solved the
pb with hdparm. 
S.