Preclear.sh results - Questions about your results? Post them here.

[Bagpuss]

Thanks very much for the rapid reply.

I think I'll run another pre-clear on that drive, and then monitor it closely.

 

[Joe L.]

Thanks very much for the rapid reply.

I think I'll run another pre-clear on that drive, and then monitor it closely.

Smething happened prior to the preclear to mark those sectors as having a checksum at the end of the sector that did not match the contents of the sector.

As already mentioned, they were re-written in place, and the contents then matched the expected checksum for those 7 sectors.

 

A subsequent preclear cycle will tell you more.  With any luck you'll not see any additional un-readable sectors

(all checksums at ends of sectors will match the contents of their affiliated sector)

 

Joe L.

[guitarlp]

What does it mean if the records in and records out values contain a positive + value? For example, I'm current preclearing a 3TB WD Red drive that shows the following:

 

624648+4 records in

624648+4 records out

 

What's the +4 value? Is that a bad sign?

 

Edit:

 

Now they're at +6:

 

660271+6 records in

660271+6 records out

[garycase]

What does it mean if the records in and records out values contain a positive + value? For example, I'm current preclearing a 3TB WD Red drive that shows the following:

 

624648+4 records in

624648+4 records out

 

What's the +4 value? Is that a bad sign?

 

Edit:

 

Now they're at +6:

 

660271+6 records in

660271+6 records out

 

What did the pre-clear report show at the end of this pre-clear?  I've never noticed this (don't usually watch the pre-clear until it's done) ... but now that you noted it, I undoubtedly will on my next pre-clear      And of course I'll wonder the same thing if the "+" number is anything but zero !!

 

I'm surprised Joe L  didn't provide some feedback on this.  Joe L ??

 

[guitarlp]

What does it mean if the records in and records out values contain a positive + value? For example, I'm current preclearing a 3TB WD Red drive that shows the following:

 

624648+4 records in

624648+4 records out

 

What's the +4 value? Is that a bad sign?

 

Edit:

 

Now they're at +6:

 

660271+6 records in

660271+6 records out

 

What did the pre-clear report show at the end of this pre-clear?  I've never noticed this (don't usually watch the pre-clear until it's done) ... but now that you noted it, I undoubtedly will on my next pre-clear      And of course I'll wonder the same thing if the "+" number is anything but zero !!

 

I'm surprised Joe L  didn't provide some feedback on this.  Joe L ??

 

I did the pre-clear on two drives and both of them had increasing "+" values as the pre-clear continued. The reports at the end showed no issues on either drive. I checked the Smart reports before and after and didn't see anything concerning.

 

So for those that see this, I don't believe it's anything to worry about. I'd still like to know what it means though because it did concern me to see a number increasing during a pre-clear like that. I assumed it was bad sectors getting replaced or something of the sort. Trying to google for what it means didn't return anything relevant.

[garycase]

I'd still like to know what it means though ...

 

Ditto.  I've got some new drives coming next week, so will definitely look to see if they have the same "+" numbers.    And while I'll trust the SMART reports and final Pre-Clear results page, like you I'd just like to know what these numbers are reporting 

 

[Joe L.]

They are just the statistics reported by the "dd" command.  I never cared what they meant (was more interested in the number of blocks read).  Probably indicates some partial blocks of bytes.  (nothing to worry about)  You would have to look up the "dd" command to learn more.

 

Joe L.

[garycase]

Thanks Joe.  I may do a bit of reading on dd,  but the real bottom line is ...

 

    If you don't care about those numbers, neither do I !!  :)

[Joe L.]

They are just the statistics reported by the "dd" command.  I never cared what they meant (was more interested in the number of blocks read).  Probably indicates some partial blocks of bytes.  (nothing to worry about)  You would have to look up the "dd" command to learn more.

 

Joe L.

I did some research.  The number after the "+" is the number of partial blocks read or written.  Since the pre-clear script periodically sends a query to the process actually writing a disk that is using "dd", and has no way to synchronize the request, it is possible to get a response while in the middle of writing a "block" of data.    For that reason you'll see the +n increment over time.  It is just a measure of how many times you managed to ask its percentage complete when it was in the middle of writing a block of data.

 

Joe L.

[garycase]

Thanks Joe.  Nice to know it's that simple.

 

[Beer40oz]

It's my hard drive ready?

preclear_finish__W1H1P1ZV_2013-07-24.txt

preclear_start__W1H1P1ZV_2013-07-24.txt

[Joe L.]

It's my hard drive ready?

Where's the report showing the changes?

 

The high-fly-writes went from 100 to 75 during the pre-clear.  Although nowhere near the failure threshold, keep an eye on it in the next few months.

[Beer40oz]

It's my hard drive ready?

Where's the report showing the changes?

 

The high-fly-writes went from 100 to 75 during the pre-clear.  Although nowhere near the failure threshold, keep an eye on it in the next few months.

 

Thanx Joe .... I will add it to the array now to replace another failing hd.

 

What is a high-fly?  should I be worried?  I will keep an eye on it the next few months. Sorry here is the report forgot there where 3 files.

preclear_rpt__W1H1P1ZV_2013-07-24.txt

[Joe L.]

It's my hard drive ready?

Where's the report showing the changes?

 

The high-fly-writes went from 100 to 75 during the pre-clear.  Although nowhere near the failure threshold, keep an eye on it in the next few months.

 

Thanx Joe .... I will add it to the array now to replace another failing hd.

 

What is a high-fly?  should I be worried?  I will keep an eye on it the next few months. Sorry here is the report forgot there where 3 files.

From the SMART Wiki:

High Fly Writes

HDD producers implement a Fly Height Monitor that attempts to provide additional protections for write operations by detecting when a recording head is flying outside its normal operating range. If an unsafe fly height condition is encountered, the write process is stopped, and the information is rewritten or reallocated to a safe region of the hard drive. This attribute indicates the count of these errors detected over the lifetime of the drive.

 

This feature is implemented in most modern Seagate drives[1] and some of Western Digital’s drives, beginning with the WD Enterprise WDE18300 and WDE9180 Ultra2 SCSI hard drives, and will be included on all future WD Enterprise products.[20]

 

[Beer40oz]

Joe why is it then my 1 Raw_Read_Error_Rate  is so high from all my other drives?  something to worry about? thank you.

[RobJ]

Joe why is it then my 1 Raw_Read_Error_Rate  is so high from all my other drives?  something to worry about? thank you.

 

Perhaps I could help with that?  I've started a page, very incomplete yet, but does have comments specific to the Raw Read Error Rate.

 

A comment about the High Fly Writes attribute - ignore the VALUE and WORST for this attribute.  I believe it has a dummy routine attached to it, because in all cases I have seen, it behaves like the following:

 

++RAW[189];  // it's a counter for high fly writes
if (VALUE[189] > 1)  --VALUE[189];  // decrement for each event (drops it from 100 down to 1), but no lower than 1
if (WORST[189] > VALUE[189])  WORST[189] = VALUE[189];  // the usual statement setting WORST to the lowest value of VALUE

 

RAW appears to be the true counter of High Fly Write events.  VALUE then becomes 100 - RAW until RAW exceeds 99, and then VALUE and WORST are stuck at 1, and never can reach THRESH of 0.  That's why I believe it is an experimental attribute and this is a dummy routine, and should be ignored.  However, the fact that there are High Fly Writes occurring may be of note, should probably be monitored, but we have no guidance anywhere as to their significance.

[Bagpuss]

Hi All,

 

I've just done a preclear on a 120GB 2.5" drive that I was intending to use as a cache drive in a small unRAID system that I'm building for a friend.

I've done 3 pre-clear cycles on the drive, and on each subsequent cycle, the number of sectors pending re-allocation has increased by 112.

 

I've attached the pre-clear reports, and would appreciate an opinion on the condition of this drive.

 

Thanks,

 

Andy.

preclear_rpt__S14PJD0Q752009_2013-07-25.txt

preclear_start__S14PJD0Q752009_2013-07-25.txt

preclear_finish__S14PJD0Q752009_2013-07-25.txt

[Beer40oz]

Joe why is it then my 1 Raw_Read_Error_Rate  is so high from all my other drives?  something to worry about? thank you.

 

Perhaps I could help with that?  I've started a page, very incomplete yet, but does have comments specific to the Raw Read Error Rate.

 

A comment about the High Fly Writes attribute - ignore the VALUE and WORST for this attribute.  I believe it has a dummy routine attached to it, because in all cases I have seen, it behaves like the following:

 

++RAW[189];  // it's a counter for high fly writes
if (VALUE[189] > 1)  --VALUE[189];  // decrement for each event (drops it from 100 down to 1), but no lower than 1
if (WORST[189] > VALUE[189])  WORST[189] = VALUE[189];  // the usual statement setting WORST to the lowest value of VALUE

 

RAW appears to be the true counter of High Fly Write events.  VALUE then becomes 100 - RAW until RAW exceeds 99, and then VALUE and WORST are stuck at 1, and never can reach THRESH of 0.  That's why I believe it is an experimental attribute and this is a dummy routine, and should be ignored.  However, the fact that there are High Fly Writes occurring may be of note, should probably be monitored, but we have no guidance anywhere as to their significance.

 

Thank you RobJ 

[RobJ]

I've just done a preclear on a 120GB 2.5" drive that I was intending to use as a cache drive in a small unRAID system that I'm building for a friend.

I've done 3 pre-clear cycles on the drive, and on each subsequent cycle, the number of sectors pending re-allocation has increased by 112.

 

I've attached the pre-clear reports, and would appreciate an opinion on the condition of this drive.

 

I can't help being a little suspicious of these SMART numbers.  Attributes 196, 197, and 198 are all increasing by significant amounts, yet there are no remapped sectors and no SMART errors logged.  It says 375 hours on the drive, is that plausible?  I note that it indicates there have been 3 times as many power cycles of the drive as there have been operational hours.  That is, for every hour it has been on, it thinks it has been turned on 3 times each hour?!?  I suppose that is possible if this was in a laptop used for a number of short sessions (turn on, check email, turn off), or perhaps aggressive power-saving (quick turn off of hard drive when idle).

 

I recommend running a SMART long test, to see if it will reset some of the SMART attributes.  Then post a subsequent SMART report.  If we can get it to reset, and it looks OK, then you will need at least one more Preclear before you can trust this drive.

[Bagpuss]

 

I can't help being a little suspicious of these SMART numbers.  Attributes 196, 197, and 198 are all increasing by significant amounts, yet there are no remapped sectors and no SMART errors logged.  It says 375 hours on the drive, is that plausible?  I note that it indicates there have been 3 times as many power cycles of the drive as there have been operational hours.  That is, for every hour it has been on, it thinks it has been turned on 3 times each hour?!?  I suppose that is possible if this was in a laptop used for a number of short sessions (turn on, check email, turn off), or perhaps aggressive power-saving (quick turn off of hard drive when idle).

 

I recommend running a SMART long test, to see if it will reset some of the SMART attributes.  Then post a subsequent SMART report.  If we can get it to reset, and it looks OK, then you will need at least one more Preclear before you can trust this drive.

 

Thanks for getting back to me, Rob.

 

With regards to the operational hours etc., then it's entirely possible that these figures are accurate, as the drive was a pull from a defunct primary (elementary) school laptop. It's quite likely that it could have been turned on and off regulary in very short sessions.

 

I'll try running a long SMART test, and see what happens.

 

[Bagpuss]

Hi Rob,

 

Attached is a SMART report after a long SMART test.

 

There doesn't appear to be much different in the report that I can see, apart from certain error counts going up.

Would really appreciate it if you could take a look at the new report.

 

Thanks,

 

Andy.

smart.afterlongtest.txt

[RobJ]

Hi Rob,

 

Attached is a SMART report after a long SMART test.

 

There doesn't appear to be much different in the report that I can see, apart from certain error counts going up.

Would really appreciate it if you could take a look at the new report.

 

Thanks,

 

Andy.

 

Very interesting drive.  It is not behaving in a standard way, so my comments should be treated as low confidence, as I've never seen a drive like this.

 

Current_Pending_Sector count did not change, did not increase because long test does not write, but I was hoping it would drop, perhaps even clear completely.  Reallocated_Event_Count increased by 58, yet there are no remapped sectors and no logged errors.  Offline_Uncorrectable increased by 112.

 

Your previous Preclear caused Current_Pending_Sector count to increase by 112, Reallocated_Event_Count to increase by 183 (an average of 61 per Preclear pass), and Offline_Uncorrectable to increase by 336 (112 times 3, 112 per Preclear pass).

 

It's very difficult to trust this drive, but I can't actually say it's bad, with no errors logged and no critical attribute values (those marked Prefail).

 

Try one more Preclear.  You might also look for a firmware update from Samsung.

[Bagpuss]

Very interesting drive.  It is not behaving in a standard way, so my comments should be treated as low confidence, as I've never seen a drive like this.

 

Current_Pending_Sector count did not change, did not increase because long test does not write, but I was hoping it would drop, perhaps even clear completely.  Reallocated_Event_Count increased by 58, yet there are no remapped sectors and no logged errors.  Offline_Uncorrectable increased by 112.

 

Your previous Preclear caused Current_Pending_Sector count to increase by 112, Reallocated_Event_Count to increase by 183 (an average of 61 per Preclear pass), and Offline_Uncorrectable to increase by 336 (112 times 3, 112 per Preclear pass).

 

It's very difficult to trust this drive, but I can't actually say it's bad, with no errors logged and no critical attribute values (those marked Prefail).

 

Try one more Preclear.  You might also look for a firmware update from Samsung.

 

I'm glad to hear you say that. I was genuinely confused by what it's doing.

 

I'll give it one more preclear, and see what happens. I've not had chance to look for a firmware update, so I'll give that a try too.

At the end of the day, it's a recycled drive from an old Dell laptop, so no great loss if it doesn't work.

 

Thanks again for your help.

 

[RobJ]

Just my opinion, and not an expert one at that, I don't see any evidence that those number changes actually relate to real physical errors.  The Preclear pass times look quick for a relatively slow drive, so no indication of any slowdowns while testing marginal sectors.  There are no Preclear failures, the zeroing and post-reads are successful, so no indication of any hard drive problems.  SMART reports no remapped sectors at all, no SMART errors in its log, and all critical attributes appear near perfect, or at least error-free.  And the number changes seem to fit a software pattern, not a random hardware pattern as you would expect.  It's hard for me not to feel that the firmware is either buggy, or has been corrupted, which is why I suggested a check for a firmware update, admittedly a long shot.  If the subsequent Preclear is similar, then I don't know what to advise, because while I feel the drive is probably physically fine, buggy or corrupted firmware or SMART subsystem makes the drive somewhat untrustable.

[garycase]

I'm in the process of pre-clearing several new 4TB Seagate NAS drives, and have the following results from the first 2 drives (the two sets of results are nearly identical, so I've only listed one, as it shows what I'd like to know).

 

I'd appreciate some feedback on the results.    My thoughts/questions are as follows:

 

(1)  The Raw Read Error Rate actually shows improvement (from 100 to 110), so I assume it's fine, and I should simply ignore the raw value.    Is that correct?

 

(2)  Both the Spin Retry Count and End-to-End Error values are the same (100 before, 100 after), but the status shows "Near Threshold".  Any comment on these?  ... or are they fine and "ignorable" ??

 

(3)  From what I've read earlier in this thread, I assume I should simply ignore the High Fly Writes.  [status shows "Ok" anyway]

 

(4)  The temps seem fine.  Not sure why the airflow is shown as "Near Threshold", but I don't see anything to worry about -- agree?

 

 

** Changed attributes in files: /tmp/smart_start_sdb  /tmp/smart_finish_sdb

                ATTRIBUTE  NEW_VAL OLD_VAL FAILURE_THRESHOLD STATUS      RAW_VALUE

      Raw_Read_Error_Rate =  110    100            6        ok                              26923560

            Spin_Retry_Count =  100    100          97        near_thresh                            0

            End-to-End_Error =  100    100          99        near_thresh                            0

              High_Fly_Writes =    34    100            0        ok                                        66

  Airflow_Temperature_Cel =    70      71          45        near_thresh                          30

        Temperature_Celsius =    30      29            0          ok                                        30

No SMART attributes are FAILING_NOW