From Newsgroup: comp.sys.raspberry-pi

I've got a couple of old-ish Pi2 v1.1 32 bit hosts. Both
have started to behave strangely, one having trouble booting
and the other reporting what could be thought of as "off by one"
errors that cause processes to report errors.

They're the first two Pi2s purchased, in 2015. They've been
powered on close to 24/7 since and I'm starting to wonder
if they're wearing out. I didn't think it possible, but I'm
running out of other ideas that make sense.

Is there a hardware test suite for the Raspberry Pi that can
identify faulty hardware? I know, this sounds a bit like the
halting problem, which is insoluble, but I think it's slightly
more tractable, maybe. Perhaps what I'm looking for is a kind
of fuzzing test, though fuzzing usually tests software error
handling and I'm looking for hardware errors (I think!).

Test suites for i386 PCs used to be common, especially for
memory. Something similar for the Pi2 would be a start.

Thanks for reading,

bob prohaska



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From Newsgroup: comp.sys.raspberry-pi

On 19/06/2024 22:56, bp@www.zefox.net wrote:

I've got a couple of old-ish Pi2 v1.1 32 bit hosts. Both
have started to behave strangely, one having trouble booting
and the other reporting what could be thought of as "off by one"
errors that cause processes to report errors.

They're the first two Pi2s purchased, in 2015. They've been
powered on close to 24/7 since and I'm starting to wonder
if they're wearing out. I didn't think it possible, but I'm
running out of other ideas that make sense.

Is there a hardware test suite for the Raspberry Pi that can
identify faulty hardware? I know, this sounds a bit like the
halting problem, which is insoluble, but I think it's slightly
more tractable, maybe. Perhaps what I'm looking for is a kind
of fuzzing test, though fuzzing usually tests software error
handling and I'm looking for hardware errors (I think!).

Test suites for i386 PCs used to be common, especially for
memory. Something similar for the Pi2 would be a start.

Thanks for reading,

bob prohaska

The only item that I would suspect has 'wear' issues would be the SD cards.
--
“Some people like to travel by train because it combines the slowness of
a car with the cramped public exposure of 
an airplane.”

Dennis Miller


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From Newsgroup: comp.sys.raspberry-pi

On 20/06/2024 06:49, The Natural Philosopher wrote:

Test suites for i386 PCs used to be common, especially for
memory. Something similar for the Pi2 would be a start.

Thanks for reading,

bob prohaska

The only item that I would suspect has 'wear' issues would be the SD cards.

We always suspect SD cards, rightly so, but it could be other stuff. It
is quite common for routers to die of old age.

A quick google reveals there are test tools, such as memtest, or maybe stress-ng.






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From Newsgroup: comp.sys.raspberry-pi

On 20/06/2024 07:12, Pancho wrote:

On 20/06/2024 06:49, The Natural Philosopher wrote:

Test suites for i386 PCs used to be common, especially for
memory. Something similar for the Pi2 would be a start.

Thanks for reading,

bob prohaska

The only item that I would suspect has 'wear' issues would be the SD
cards.

We always suspect SD cards, rightly so, but it could be other stuff. It
is quite common for routers to die of old age.

Only time I have had routers fail is after lightning strikes on or near
DSL lines

A quick google reveals there are test tools, such as memtest, or maybe stress-ng.

Well all semiconductors are subject to dopant migration and/or
contamination after sealing failures. Especially at elevated
temperatures. But since nothing on a Pi is 'user replaceable' knowing
what is faulty is of academic interest only.

SD cards are cheap and so are Pis. selective replacement would seem to
be a simpler method to achieve a working setup again.
--
"It is an established fact to 97% confidence limits that left wing conspirators see right wing conspiracies everywhere"

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From Newsgroup: comp.sys.raspberry-pi

<bp@www.zefox.net> writes:

I've got a couple of old-ish Pi2 v1.1 32 bit hosts. Both
have started to behave strangely, one having trouble booting
and the other reporting what could be thought of as "off by one"
errors that cause processes to report errors.

I don’t know of a test suite as such but if it can’t reliably boot a
Linux kernel from known-good storage (e.g. fresh install on a uSD card)
then you’ve got the core of your answer: it’s broken.

As others have said, SD card failure should be right at the top of the
list of possible causes.

“Processes reporting errors” is harder to assess with so little information, certainly there’s not enough presented here to assume a
hardware fault.

They're the first two Pi2s purchased, in 2015. They've been
powered on close to 24/7 since and I'm starting to wonder
if they're wearing out. I didn't think it possible, but I'm
running out of other ideas that make sense.

Is there a hardware test suite for the Raspberry Pi that can
identify faulty hardware? I know, this sounds a bit like the
halting problem, which is insoluble, but I think it's slightly
more tractable, maybe. Perhaps what I'm looking for is a kind
of fuzzing test, though fuzzing usually tests software error
handling and I'm looking for hardware errors (I think!).

Fuzzing is a technique for discovering bugs you didn’t yet know
existed. In this case it seems you can already reproduce the issues...
--
https://www.greenend.org.uk/rjk/
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From Newsgroup: comp.sys.raspberry-pi

On 20/06/2024 08:44, The Natural Philosopher wrote:

On 20/06/2024 07:12, Pancho wrote:

On 20/06/2024 06:49, The Natural Philosopher wrote:

Test suites for i386 PCs used to be common, especially for
memory. Something similar for the Pi2 would be a start.

Thanks for reading,

bob prohaska

The only item that I would suspect has 'wear' issues would be the SD
cards.

We always suspect SD cards, rightly so, but it could be other stuff.
It is quite common for routers to die of old age.

Only time I have had routers fail is after lightning strikes on or near
DSL lines

I've had failures to: ADSL router, VDSL modem, cable router. I dunno
what goes wrong, but these are devices running close to design capacity
for many years. Whereas most desktop PCs rarely break a sweat. We know electronic components like electrolytic capacitors do wear out.

Which reminds me, an even more common failure is USB wall warts, that
probably should show up in dmesg or journalctl as an "under voltage" error.


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From Newsgroup: comp.sys.raspberry-pi

On Thu, 2024-06-20 at 06:49 +0100, The Natural Philosopher wrote:

The only item that I would suspect has 'wear' issues would be the SD
cards.

We have smartctl for SATA and NVME drives, that tells us how healthy
these devices are. Is there something similar for SD cards?
--
Tactical Nuclear Kittens
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From Newsgroup: comp.sys.raspberry-pi

Single Stage to Orbit <alex.buell@munted.eu> wrote:

On Thu, 2024-06-20 at 06:49 +0100, The Natural Philosopher wrote:

The only item that I would suspect has 'wear' issues would be the SD
cards.

We have smartctl for SATA and NVME drives, that tells us how healthy
these devices are. Is there something similar for SD cards?

Only tools that will write data to them and then read it back to
check if the data is still correct. There's no standard like SMART
for them the SD card controller to report stats back over the card
interface.
--
__ __
#_ < |\| |< _#
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From Newsgroup: comp.sys.raspberry-pi

On 21 Jun 2024 09:08:06 +1000, Computer Nerd Kev wrote:

There's no standard like SMART for them
the SD card controller to report stats back over the card interface.

SMART isn’t much use, anyway. I test my storage devices for actual I/O errors.
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From Newsgroup: comp.sys.raspberry-pi

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

On 21 Jun 2024 09:08:06 +1000, Computer Nerd Kev wrote:

There's no standard like SMART for them
the SD card controller to report stats back over the card interface.

SMART isn’t much use, anyway. I test my storage devices for actual I/O errors.

That's what you use SMART *for*. Amongst other things
--
Karl Marx said religion is the opium of the people.
But Marxism is the crack cocaine.

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From Newsgroup: comp.sys.raspberry-pi

On Tue, 16 Jul 2024 10:31:11 +0100, The Natural Philosopher wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

SMART isn’t much use, anyway. I test my storage devices for actual I/O
errors.

That's what you use SMART *for*.

No, I test doing actual I/O.
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From Newsgroup: comp.sys.raspberry-pi

On 17/07/2024 02:30, Lawrence D'Oliveiro wrote:

On Tue, 16 Jul 2024 10:31:11 +0100, The Natural Philosopher wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

SMART isn’t much use, anyway. I test my storage devices for actual I/O >>> errors.

That's what you use SMART *for*.

No, I test doing actual I/O.

So does SMART.

And with SSDS you dont want to be actually doing any superfluous read or
write ops
I am curious. Have you ever used SMART at all?
--
“It is not the truth of Marxism that explains the willingness of intellectuals to believe it, but the power that it confers on
intellectuals, in their attempts to control the world. And since...it is futile to reason someone out of a thing that he was not reasoned into,
we can conclude that Marxism owes its remarkable power to survive every criticism to the fact that it is not a truth-directed but a
power-directed system of thought.”
Sir Roger Scruton

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From Newsgroup: comp.sys.raspberry-pi

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

On 21 Jun 2024 09:08:06 +1000, Computer Nerd Kev wrote:

There's no standard like SMART for them
the SD card controller to report stats back over the card interface.

SMART isn’t much use, anyway. I test my storage devices for actual I/O errors.

By the time any type of storage device is reporting errors during actual
use, it's already in a really bad way, and should have been replaced.

Both spinning discs and flash media are over provisioned with a number
of spare sectors/blocks which they will silently map in, either over
sectors which have started giving read errors, or any flash blocks which
have reached their write limits and could be unreliable.

The SMART information on the drive will tell you when this happens, long before the OS finds the disc has started to be come corrupted. Use this
as the first warning to replace the disc before data loss or complete
failure.

---druck
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From Newsgroup: comp.sys.raspberry-pi

On 17/07/2024 12:10, druck wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

On 21 Jun 2024 09:08:06 +1000, Computer Nerd Kev wrote:

There's no standard like SMART for them
the SD card controller to report stats back over the card interface.

SMART isn’t much use, anyway. I test my storage devices for actual I/O
errors.

By the time any type of storage device is reporting errors during actual use, it's already in a really bad way, and should have been replaced.

Both spinning discs and flash media are over provisioned with a number
of spare sectors/blocks which they will silently map in, either over
sectors which have started giving read errors, or any flash blocks which have reached their write limits and could be unreliable.

The SMART information on the drive will tell you when this happens, long before the OS finds the disc has started to be come corrupted. Use this
as the first warning to replace the disc before data loss or complete failure.

---druck

Exactly.
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE
UPDATED WHEN_FAILED RAW_VALUE
1 Raw_Read_Error_Rate 0x0032 100 100 050 Old_age
Always - 0
5 Reallocated_Sector_Ct 0x0032 100 100 050 Old_age
Always - 0
9 Power_On_Hours 0x0032 100 100 050 Old_age
Always - 23833
12 Power_Cycle_Count 0x0032 100 100 050 Old_age
Always - 113
160 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 0
161 Unknown_Attribute 0x0033 100 100 050 Pre-fail Always
- 100
163 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 8
164 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 70687
165 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 326
166 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 115
167 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 142
168 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 7000
169 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 98
175 Program_Fail_Count_Chip 0x0032 100 100 050 Old_age Always
- 0
176 Erase_Fail_Count_Chip 0x0032 100 100 050 Old_age Always
- 0
177 Wear_Leveling_Count 0x0032 100 100 050 Old_age Always
- 0
178 Used_Rsvd_Blk_Cnt_Chip 0x0032 100 100 050 Old_age Always
- 0
181 Program_Fail_Cnt_Total 0x0032 100 100 050 Old_age Always
- 0
182 Erase_Fail_Count_Total 0x0032 100 100 050 Old_age Always
- 0
192 Power-Off_Retract_Count 0x0032 100 100 050 Old_age Always
- 51
194 Temperature_Celsius 0x0022 100 100 050 Old_age Always
- 40
195 Hardware_ECC_Recovered 0x0032 100 100 050 Old_age Always
- 1397810
196 Reallocated_Event_Count 0x0032 100 100 050 Old_age Always
- 0
197 Current_Pending_Sector 0x0032 100 100 050 Old_age Always
- 0
198 Offline_Uncorrectable 0x0032 100 100 050 Old_age Always
- 0
199 UDMA_CRC_Error_Count 0x0032 100 100 050 Old_age Always
- 0
232 Available_Reservd_Space 0x0032 100 100 050 Old_age Always
- 100
241 Total_LBAs_Written 0x0030 100 100 050 Old_age
Offline - 247432
242 Total_LBAs_Read 0x0030 100 100 050 Old_age
Offline - 56254
245 Unknown_Attribute 0x0032 100 100 050 Old_age Always
- 346410

Raw error read read is there, also something you wouldn't find outside
SMART - reallocated sector count plus erase fail and wear levelling counts
--
Ideas are more powerful than guns. We would not let our enemies have
guns, why should we let them have ideas?

Josef Stalin

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From Newsgroup: comp.sys.raspberry-pi

On Wed, 17 Jul 2024 10:35:01 +0100, The Natural Philosopher wrote:

On 17/07/2024 02:30, Lawrence D'Oliveiro wrote:

On Tue, 16 Jul 2024 10:31:11 +0100, The Natural Philosopher wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

SMART isn’t much use, anyway. I test my storage devices for actual
I/O errors.

That's what you use SMART *for*.

No, I test doing actual I/O.

So does SMART.

No, it extrapolates from its internal firmware behaviour. It tries to
predict failures before they happen.
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From Newsgroup: comp.sys.raspberry-pi

On Wed, 17 Jul 2024 12:10:22 +0100, druck wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

On 21 Jun 2024 09:08:06 +1000, Computer Nerd Kev wrote:

There's no standard like SMART for them the SD card controller to
report stats back over the card interface.

SMART isn’t much use, anyway. I test my storage devices for actual I/O
errors.

By the time any type of storage device is reporting errors during actual
use, it's already in a really bad way, and should have been replaced.

This is why you have redundant systems. That’s how the pros do it.
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From Newsgroup: comp.sys.raspberry-pi

On 21/07/2024 09:05, Lawrence D'Oliveiro wrote:

On Wed, 17 Jul 2024 10:35:01 +0100, The Natural Philosopher wrote:

On 17/07/2024 02:30, Lawrence D'Oliveiro wrote:

On Tue, 16 Jul 2024 10:31:11 +0100, The Natural Philosopher wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

SMART isn’t much use, anyway. I test my storage devices for actual >>>>> I/O errors.

That's what you use SMART *for*.

No, I test doing actual I/O.

So does SMART.

No, it extrapolates from its internal firmware behaviour. It tries to
predict failures before they happen.

No it doesn't. It predicts from stored values of errors. I/O amongst them

Do try to keep up.
--
If I had all the money I've spent on drink...
..I'd spend it on drink.

Sir Henry (at Rawlinson's End)

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From Newsgroup: comp.sys.raspberry-pi

On 21/07/2024 09:06, Lawrence D'Oliveiro wrote:

On Wed, 17 Jul 2024 12:10:22 +0100, druck wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

On 21 Jun 2024 09:08:06 +1000, Computer Nerd Kev wrote:

There's no standard like SMART for them the SD card controller to
report stats back over the card interface.

SMART isn’t much use, anyway. I test my storage devices for actual I/O >>> errors.

By the time any type of storage device is reporting errors during actual
use, it's already in a really bad way, and should have been replaced.

This is why you have redundant systems. That’s how the pros do it.

No. Its why you use SMART.

AND redundant storage, which SSDs already have built in
--
WOKE is an acronym... Without Originality, Knowledge or Education.

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From Newsgroup: comp.sys.raspberry-pi

On Sun, 21 Jul 2024 09:31:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

On 21/07/2024 09:06, Lawrence D'Oliveiro wrote:

On Wed, 17 Jul 2024 12:10:22 +0100, druck wrote:

By the time any type of storage device is reporting errors during
actual use, it's already in a really bad way, and should have been
replaced.

This is why you have redundant systems. That’s how the pros do it.

No. Its why you use SMART.

AND redundant storage, which SSDs already have built in

Yes but the kind of redundancy I thought of first was some kind of
RAID or live backup (I do both and monitor SMART) so that there isn't just
one copy of the data ready to be used.
--
Steve O'Hara-Smith
Odds and Ends at http://www.sohara.org/
For forms of government let fools contest
Whate're is best administered is best - Alexander Pope
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From Newsgroup: comp.sys.raspberry-pi

On 21/07/2024 10:22, Ahem A Rivet's Shot wrote:

On Sun, 21 Jul 2024 09:31:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

On 21/07/2024 09:06, Lawrence D'Oliveiro wrote:

On Wed, 17 Jul 2024 12:10:22 +0100, druck wrote:

By the time any type of storage device is reporting errors during
actual use, it's already in a really bad way, and should have been
replaced.

This is why you have redundant systems. That’s how the pros do it.

No. Its why you use SMART.

AND redundant storage, which SSDs already have built in

Yes but the kind of redundancy I thought of first was some kind of
RAID or live backup (I do both and monitor SMART) so that there isn't just one copy of the data ready to be used.

Oh indeed. My new server will feature two SMART enabled SSDs...one a
mirror of the other.
I am not interested in RAID. RAID increases availability, but does not
archive data
--
Labour - a bunch of rich people convincing poor people to vote for rich
people by telling poor people that "other" rich people are the reason
they are poor.

Peter Thompson

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From Newsgroup: comp.sys.raspberry-pi

On Sun, 21 Jul 2024 10:44:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

Oh indeed. My new server will feature two SMART enabled SSDs...one a
mirror of the other.
I am not interested in RAID. RAID increases availability, but does not archive data

You have a mirror - that's RAID. RAID is about smoothly surviving
drive failures. With any storage system there are two important factors -
mean time to data loss and probability of data unavailability.

My NAS has two mirrored 1TB NVMe SSDs and two 10TB mirrored hard
discs holding ZFS filesystems with regular snapshots enabled - the archive server has four 4TB hard discs in a ZFS RAIDZ1 (FEC RAID with 3 data and 1 parity) - it's also in a different building. There is a continuous cycle to
the archive server keeping the archive up to date within a minute or two.

End result
- Fast and slow (relatively) stores
- Snapshots for protection against silliness or corruption
- RAID for protection against drive failure
- Archive for protection against machine/building loss

According to an MTTDL calculator I found once (no idea how
trustworthy it is) I should be good for about a century.
--
Steve O'Hara-Smith
Odds and Ends at http://www.sohara.org/
For forms of government let fools contest
Whate're is best administered is best - Alexander Pope
--- Synchronet 3.19b-Win32 NewsLink 1.113

From Newsgroup: comp.sys.raspberry-pi

On 21/07/2024 11:47, Ahem A Rivet's Shot wrote:

On Sun, 21 Jul 2024 10:44:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

Oh indeed. My new server will feature two SMART enabled SSDs...one a
mirror of the other.
I am not interested in RAID. RAID increases availability, but does not
archive data

You have a mirror - that's RAID.

No, it is not RAID.

I back up once a night. In between if I erase a file its still there on
the backup
That is not RAID
--
Gun Control: The law that ensures that only criminals have guns.

--- Synchronet 3.19b-Win32 NewsLink 1.113

From Newsgroup: comp.sys.raspberry-pi

On Sun, 21 Jul 2024 15:52:36 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

On 21/07/2024 11:47, Ahem A Rivet's Shot wrote:

On Sun, 21 Jul 2024 10:44:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

Oh indeed. My new server will feature two SMART enabled SSDs...one a
mirror of the other.
I am not interested in RAID. RAID increases availability, but does not
archive data

You have a mirror - that's RAID.

No, it is not RAID.

I back up once a night. In between if I erase a file its still there on
the backup
That is not RAID

Ah - it's not a mirror then either it's a backup copy.
--
Steve O'Hara-Smith
Odds and Ends at http://www.sohara.org/
For forms of government let fools contest
Whate're is best administered is best - Alexander Pope
--- Synchronet 3.19b-Win32 NewsLink 1.113

From Newsgroup: comp.sys.raspberry-pi

On 21/07/2024 16:06, Ahem A Rivet's Shot wrote:

On Sun, 21 Jul 2024 15:52:36 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

On 21/07/2024 11:47, Ahem A Rivet's Shot wrote:

On Sun, 21 Jul 2024 10:44:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

Oh indeed. My new server will feature two SMART enabled SSDs...one a
mirror of the other.
I am not interested in RAID. RAID increases availability, but does not >>>> archive data

You have a mirror - that's RAID.

No, it is not RAID.

I back up once a night. In between if I erase a file its still there on
the backup
That is not RAID

Ah - it's not a mirror then either it's a backup copy.

--
"In our post-modern world, climate science is not powerful because it is
true: it is true because it is powerful."

Lucas Bergkamp

--- Synchronet 3.19b-Win32 NewsLink 1.113

From Newsgroup: comp.sys.raspberry-pi

On 21/07/2024 11:47, Ahem A Rivet's Shot wrote:

On Sun, 21 Jul 2024 10:44:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

Oh indeed. My new server will feature two SMART enabled SSDs...one a
mirror of the other.
I am not interested in RAID. RAID increases availability, but does not
archive data

You have a mirror - that's RAID. RAID is about smoothly surviving
drive failures. With any storage system there are two important factors - mean time to data loss and probability of data unavailability.

Ignoring whether its RAID or not, mirroring will protect you against a
random failure of one of the drives, which was more useful in the
spinning rust days when random mechanical failures were an issue.

With SSD, write life is the main issue, and if you have two identical
mirrored drives, you may find any write life issues, which are not
random, occur at exactly the same time.

So with any type of mirrored arrangement, make sure they are different
makes or models of drive, so it is less likely they fail together.

---druck


--- Synchronet 3.19b-Win32 NewsLink 1.113

From Newsgroup: comp.sys.raspberry-pi

On 21/07/2024 21:28, druck wrote:

On 21/07/2024 11:47, Ahem A Rivet's Shot wrote:

On Sun, 21 Jul 2024 10:44:03 +0100
The Natural Philosopher <tnp@invalid.invalid> wrote:

Oh indeed. My new server will feature two SMART enabled SSDs...one a
mirror of the other.
I am not interested in RAID. RAID increases availability, but does not
archive data

    You have a mirror - that's RAID. RAID is about smoothly surviving
drive failures. With any storage system there are two important factors -
mean time to data loss and probability of data unavailability.

Ignoring whether its RAID or not, mirroring will protect you against a random failure of one of the drives, which was more useful in the
spinning rust days when random mechanical failures were an issue.

I agree.

With SSD, write life is the main issue, and if you have two identical mirrored drives, you may find any write life issues, which are not
random, occur at exactly the same time.

But never at exactly the SAME time.

Remember the primary drive gets written to all day long as stuff like
this post is downmloaded, read and deleted.

The secondary gets a once a day rsync,

And, whilst I have never had an SSD wear out fromn writes in the past 8
years I have had one fail in a quite different way shortly after purchase.

So with any type of mirrored arrangement, make sure they are different
makes or models of drive, so it is less likely they fail together.

They are not subject to the same usage pattern, and they are not made
from the same components.

As long as they dont fail within 24 hours of each other
--
In a Time of Universal Deceit, Telling the Truth Is a Revolutionary Act.

- George Orwell

--- Synchronet 3.19b-Win32 NewsLink 1.113

From Newsgroup: comp.sys.raspberry-pi

On Sun, 21 Jul 2024 09:29:51 +0100, The Natural Philosopher wrote:

On 21/07/2024 09:05, Lawrence D'Oliveiro wrote:

On Wed, 17 Jul 2024 10:35:01 +0100, The Natural Philosopher wrote:

On 17/07/2024 02:30, Lawrence D'Oliveiro wrote:

On Tue, 16 Jul 2024 10:31:11 +0100, The Natural Philosopher wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

SMART isn’t much use, anyway. I test my storage devices for actual >>>>>> I/O errors.

That's what you use SMART *for*.

No, I test doing actual I/O.

So does SMART.

No, it extrapolates from its internal firmware behaviour. It tries to
predict failures before they happen.

No it doesn't. It predicts ...

s/predicts/tries to predict/. It’s not a prophet, you know.

And it only catches about 30% of failures.
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From Newsgroup: comp.sys.raspberry-pi

On Sun, 21 Jul 2024 09:31:03 +0100, The Natural Philosopher wrote:

On 21/07/2024 09:06, Lawrence D'Oliveiro wrote:

This is why you have redundant systems. That’s how the pros do it.

No. Its why you use SMART.

Companies whose business it is to ensure data integrity do not rely on
SMART.
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From Newsgroup: comp.sys.raspberry-pi

On 24/07/2024 01:33, Lawrence D'Oliveiro wrote:

On Sun, 21 Jul 2024 09:29:51 +0100, The Natural Philosopher wrote:

On 21/07/2024 09:05, Lawrence D'Oliveiro wrote:

On Wed, 17 Jul 2024 10:35:01 +0100, The Natural Philosopher wrote:

On 17/07/2024 02:30, Lawrence D'Oliveiro wrote:

On Tue, 16 Jul 2024 10:31:11 +0100, The Natural Philosopher wrote:

On 16/07/2024 01:57, Lawrence D'Oliveiro wrote:

SMART isn’t much use, anyway. I test my storage devices for actual >>>>>>> I/O errors.

That's what you use SMART *for*.

No, I test doing actual I/O.

So does SMART.

No, it extrapolates from its internal firmware behaviour. It tries to
predict failures before they happen.

No it doesn't. It predicts ...

s/predicts/tries to predict/. It’s not a prophet, you know.

And it only catches about 30% of failures.

*plonk*
--
"Corbyn talks about equality, justice, opportunity, health care, peace, community, compassion, investment, security, housing...."
"What kind of person is not interested in those things?"

"Jeremy Corbyn?"


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From Newsgroup: comp.sys.raspberry-pi

On 24/07/2024 01:34, Lawrence D'Oliveiro wrote:

On Sun, 21 Jul 2024 09:31:03 +0100, The Natural Philosopher wrote:

On 21/07/2024 09:06, Lawrence D'Oliveiro wrote:

This is why you have redundant systems. That’s how the pros do it.

No. Its why you use SMART.

Companies whose business it is to ensure data integrity do not rely on
SMART.

No, they use hardware RAID for redundancy, extensive performance
monitoring, and retire most disks before they fail based on the small percentage of failures of thousands of other discs of the same type.

But that's not what the typical person with a Raspberry Pi and a couple
of discs is able to do. The SMART information gives valuable warning of potential failures, to ignore it would be to employ the STUPID feature
of the user.

---druck
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From Newsgroup: comp.sys.raspberry-pi

On Wed, 24 Jul 2024 21:35:02 +0100, druck wrote:

On 24/07/2024 01:34, Lawrence D'Oliveiro wrote:

Companies whose business it is to ensure data integrity do not rely on
SMART.

No, they use hardware RAID for redundancy, extensive performance
monitoring, and retire most disks before they fail based on the small percentage of failures of thousands of other discs of the same type.

Actually, no. They wait until the disks actually fail before replacing
them.

But that's not what the typical person with a Raspberry Pi and a couple
of discs is able to do. The SMART information gives valuable warning of potential failures, to ignore it would be to employ the STUPID feature
of the user.

Unfortunately, SMART only catches about 30% of potential failures. That’s why relying on it is not smart.
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From Newsgroup: comp.sys.raspberry-pi

In message <v7s77k$1v8pi$3@dont-email.me>
Lawrence D'Oliveiro <ldo@nz.invalid> wrote:

On Wed, 24 Jul 2024 21:35:02 +0100, druck wrote:

On 24/07/2024 01:34, Lawrence D'Oliveiro wrote:

Companies whose business it is to ensure data integrity do not rely on SMART.

No, they use hardware RAID for redundancy, extensive performance monitoring, and retire most disks before they fail based on the small percentage of failures of thousands of other discs of the same type.

Actually, no. They wait until the disks actually fail before replacing
them.

Anyone with any sense would replace them before the bathtub failure curve starts to rise, which is usually not long after the end of the warranty
period.

But that's not what the typical person with a Raspberry Pi and a couple
of discs is able to do. The SMART information gives valuable warning of potential failures, to ignore it would be to employ the STUPID feature of the user.

Unfortunately, SMART only catches about 30% of potential failures. That's why relying on it is not smart.

It's smarter than catching 0% of potential failures by waiting until they
have already happened.

David
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From Newsgroup: comp.sys.raspberry-pi

On Thu, 2024-07-25 at 20:20 +0100, David Higton wrote:

Actually, no. They wait until the disks actually fail before
replacing
them.

Anyone with any sense would replace them before the bathtub failure
curve starts to rise, which is usually not long after the end of the
warranty period.

In my previous job, we replaced them when they failed, not before.
Customers don't like paying for hardware that will sit there doing
nothing.
--
Tactical Nuclear Kittens
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From Newsgroup: comp.sys.raspberry-pi

On 25/07/2024 20:20, David Higton wrote:

Anyone with any sense would replace them before the bathtub failure curve starts to rise, which is usually not long after the end of the warranty period.

It entirely depends on usage pattern,. A disk which is being accessed
and having huge amounts of data written and erased, yes.

A disk in a desktop computer that loads the OS and does bugger all.
Many times longer.
--
“Ideas are inherently conservative. They yield not to the attack of
other ideas but to the massive onslaught of circumstance"

- John K Galbraith


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From Newsgroup: comp.sys.raspberry-pi

On Thu, 25 Jul 2024 20:20:38 +0100, David Higton wrote:

Anyone with any sense would replace them before the bathtub failure
curve starts to rise, which is usually not long after the end of the
warranty period.

BackBlaze is a company whose business is data integrity. Every 3 months
they publish a blog post on the reliability stats of the drives that they
use. They don’t replace drives until they fail. Individual failures have essentially zero impact on their business, while replacing drives is a
cost.

Unfortunately, SMART only catches about 30% of potential failures.
That's why relying on it is not smart.

It's smarter than catching 0% of potential failures by waiting until
they have already happened.

The problem is being caught by surprise 70% of the time.
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From Newsgroup: comp.sys.raspberry-pi

On 24/07/2024 21:35, druck wrote:

No, they use hardware RAID for redundancy, extensive performance
monitoring, and retire most disks before they fail based on the small percentage of failures of thousands of other discs of the same type.

This is informative https://www.theregister.com/2024/08/06/backblaze_sees_drive_failure_rates/

---druck

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