Howto make reiser-3.6 a bit more standby friendly?

Howto make reiser-3.6 a bit more standby friendly?

[Clemens Eisserer]

Hi there,

I am currently tinkering a idn-router which a harddrive which should
mostly be in stand-by.
However it seems the drive is rather unimpressed by a 5s timeout
setting specified with hdparm and goes in standby very seldom although
the computer is runnig 100% idle (even no isdn-services started or
anything else).

Could this be because of some journal-writeback stuff or anything like
that? Is there a way to tune ReiserFS for more standby-friendliness?

Thank you in advance, lg Clemens

Re: Howto make reiser-3.6 a bit more standby friendly?

[David Masover]

Clemens Eisserer wrote:
> Hi there,
> 
> I am currently tinkering a idn-router which a harddrive which should
> mostly be in stand-by.
> However it seems the drive is rather unimpressed by a 5s timeout
> setting specified with hdparm and goes in standby very seldom although
> the computer is runnig 100% idle (even no isdn-services started or
> anything else).
> 
> Could this be because of some journal-writeback stuff or anything like
> that? Is there a way to tune ReiserFS for more standby-friendliness?

Have you tried "-o noatime"?

Also, Reiser4 is much more standby-friendly.  If you've got the RAM, it
won't touch your disk too much.

Re: Howto make reiser-3.6 a bit more standby friendly?

[Clemens Eisserer]

Hello David and thanks a lot for answering my question.

> Have you tried "-o noatime"?
Why do you think this could help? 
Since the machine does absolutly nothing (no services, simply nothing
than a open bash).
 
> Also, Reiser4 is much more standby-friendly.  If you've got the RAM, it
> won't touch your disk too much.
Yes I know - but its a bit too complicated for me to get everything
up&running from ground up using Reiser4 since its not in the
default-kernel of debian :-(

Thanks again, lg Clemens

Re: Howto make reiser-3.6 a bit more standby friendly?

[David Masover]

Clemens Eisserer wrote:
> Hello David and thanks a lot for answering my question.
> 
> 
>>Have you tried "-o noatime"?
> 
> Why do you think this could help? 
> Since the machine does absolutly nothing (no services, simply nothing
> than a open bash).

I remember someone explaining this before.  It went something like this: 
  The atime update happens whenever something is accessed.  Something 
(/bin/atime?  not on my system) needs to be accessed in order to make 
that update.  So, every five seconds, there _will_ be a new atime that 
must be written, and since ReiserFS3 doesn't do lazy writes, it _will_ 
be flushed out to disk.  (Reiser4 would just keep it in RAM until memory 
pressure or a sync/fsync forced it out to disk.)

So, the simplest way is to do "-a noatime", unless you really need the 
atime updates.  It'll boost your performance, too...

But this is all from memory, from a long time ago.  I have no idea if 
any of the above is still true.

>>Also, Reiser4 is much more standby-friendly.  If you've got the RAM, it
>>won't touch your disk too much.
> 
> Yes I know - but its a bit too complicated for me to get everything
> up&running from ground up using Reiser4 since its not in the
> default-kernel of debian :-(

Nor Gentoo, but I use it there anyway.

Re: Howto make reiser-3.6 a bit more standby friendly?

[Clemens Eisserer]

Hi David,

> So, the simplest way is to do "-a noatime", unless you really need the
> atime updates.  It'll boost your performance, too...

Wow! To be honest I was a bit skeptic wether would work but like magic
... the drive goes into standby and wakes only up if something really
needs disk access or the kernel is swapping.
Really great - think this will really do wonders to hd lifetime :-)
Thanks!

> Nor Gentoo, but I use it there anyway.
Well I plan to switch to Gentoo soon - do you know any tutorials how
to install Gentoo on Reiser4?

Thanks for all the help, lg Clemens

Re: Howto make reiser-3.6 a bit more standby friendly?

[David Masover]

Clemens Eisserer wrote:
> Hi David,

>>Nor Gentoo, but I use it there anyway.
> 
> Well I plan to switch to Gentoo soon - do you know any tutorials how
> to install Gentoo on Reiser4?

Someone made a reiser4/amd64 livecd somewhere.  Not sure if there's a
good one with straight reiser4/x86.  But, if all else fails, just use
something like the RIP (Recovery Is Possible) cd -- Gentoo can install
from any livecd, or even another Linux, so long as you have some basic
tools like tar, bzip2, chroot, and Internet (wget).

Anyway, I don't know of anything offhand, I've always done it myself
with some pretty crazy solutions (a custom livePXE), so Google is your
friend.

Re: Howto make reiser-3.6 a bit more standby friendly?

[Christian Iversen]

On Tuesday 23 August 2005 17:51, Clemens Eisserer wrote:
> Hi David,
>
> > So, the simplest way is to do "-a noatime", unless you really need the
> > atime updates.  It'll boost your performance, too...
>
> Wow! To be honest I was a bit skeptic wether would work but like magic
> ... the drive goes into standby and wakes only up if something really
> needs disk access or the kernel is swapping.
> Really great - think this will really do wonders to hd lifetime :-)

Are you sure? Common "knowledge" (empiric and anecdotal evidence) says that a 
spin-up/spin-down cycle costs significantly more "lifetime" than running the 
drive for the same amount of time. You really have to have extremely few 
spin-ups for this to have any positive effect, IMHO. 

-- 
Regards,
Christian Iversen

Re: Howto make reiser-3.6 a bit more standby friendly?

[Clemens Eisserer]

Hi Christian,

> Are you sure? Common "knowledge" (empiric and anecdotal evidence) says that a
> spin-up/spin-down cycle costs significantly more "lifetime" than running the
> drive for the same amount of time. You really have to have extremely few
> spin-ups for this to have any positive effect, IMHO.

Never really thought about that but the machine acts as server only
during the day but also runs at night - at that time nothing at all is
done with the box so I thought it would be better to send the drive to
sleep overnight.

Thanks for this thought - I'll adjust the settings via a cron-daemon
so that the drive does not have to do unesscesary spin-ups during use.

lg Clemens

Re: Howto make reiser-3.6 a bit more standby friendly?

[Jonathan Briggs]

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On Tue, 2005-08-23 at 14:39 +0200, Clemens Eisserer wrote:
> Hi there,
> 
> I am currently tinkering a idn-router which a harddrive which should
> mostly be in stand-by.
> However it seems the drive is rather unimpressed by a 5s timeout
> setting specified with hdparm and goes in standby very seldom although
> the computer is runnig 100% idle (even no isdn-services started or
> anything else).
> 
> Could this be because of some journal-writeback stuff or anything like
> that? Is there a way to tune ReiserFS for more standby-friendliness?

Check out a script called laptop-mode.  It adjusts various parameters
including /proc/sys/vm/laptop_mode.  I use Reiser 3 on my laptop and
laptop_mode seems to work pretty well.
-- 
Jonathan Briggs <jbriggs@esoft.com>
eSoft, Inc.

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Re: Howto make reiser-3.6 a bit more standby friendly?

[Pierre Etchemaïté]

Le Tue, 23 Aug 2005 14:39:15 +0200, Clemens Eisserer <linuxhippy@gmail.com> a écrit :

> Hi there,
> 
> I am currently tinkering a idn-router which a harddrive which should
> mostly be in stand-by.
> However it seems the drive is rather unimpressed by a 5s timeout
> setting specified with hdparm and goes in standby very seldom although
> the computer is runnig 100% idle (even no isdn-services started or
> anything else).

Have you tried noflushd ?
On recent kernels, it mainly tweaks /proc/sys/vm/dirty_writeback_centisecs...