[arch-general] [arch-dev-public] Load_Cycle_Count and storage-fixup

[Stefan Erik Wilkens]

2009/10/29 Xavier <shiningxc at gmail.com>:
> On Thu, Oct 29, 2009 at 6:58 PM, Stefan Erik Wilkens
> <stefanwilkens at gmail.com> wrote:
>> Through experimentation, I suppose you can find a few values to work
>> with. From the quick glance I took at storage-fixup, it seems to
>> disable the feature completely. Does anybody know if it's more
>> advanced than this or is this the full scope of this script?
>>
>
> did you look at the config file ?
> http://git.kernel.org/?p=linux/kernel/git/tj/storage-fixup.git;a=blob_plain;f=storage-fixup.conf;hb=HEAD
>
> It contains information about known bad disk and the command to
> execute for each disk.
> The script just parses the config file, looks if your disk matches one
> from the config file, and executes the command from the config.
>

I did, yes.

it seems to do either -B 254 or 255, which disables the feature
completely. some drives disable at 254, others at 255. That seems to
be the only difference.

What michael towers is suggesting is exactly what should be done IMHO.
You can monitor though smartctl or even use smartd, accumulate data
and adjust the value to hdparm with, based on the rate that the
load_cycle value increases over time.

But, again, this leaves us with a few values we have to define as "ok".

1. how many cycles per time is good? drives are made for a certain
ammount of cycles(600.000 or 300.000 I believe), devide that against a
few years (say 5) to find a value to use as benchmark? Should we make
a difference between mobile and stationary systems?
2. we should check if the system is on battery power, that usually
means it's mobile and moving (if it's on a desk, it would be on ac).
If it is on battery power, we should take into account that more
cycles reduces poweruse and reduces the chance of damage due to
shocks. Or should we ignore that and stay with the value determined at
1 ?

As you can see, there are a few choises that really should be made by
the owner of the system.

To be honest though. Something that checks / updates to maintain a
normal load_cycle average and offers the feature to disable it
completely would be better than the current state of storage-fixup.

I can't help but feel this isn't very KISS though.

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