USB memory full

[john.h...@gmail.com]

Seems to be a bug in the latest experimental software 

Backup all ok to USB 43000 tracks 

When scanning USB stops at 25311 shows as USB memory full in debug 

John 

[Peter Lowham]

Hi John,

If you could provide some more details of the situation then that would be helpful.

B2 model

Software version (Dec 15 2021 or Jan 25 2022)

# wav, # flac, # mp3,  # aac tracks

B2 Disk space used

USB backup device size

Regards,

Peter.

[john.h...@gmail.com]

Hi latest Jan 2022 software. Using a 2tb external drive backup is complete when the 

B2 books it only scans so far on the USB then gives the error in debug 

See pictures attached 

John 

[Daniel Taylor]

It would seem that you have a fake USB stick.  

...a small applicaction called 'H2testw' which can test USB sticks and will report on the state of the stick.

Peter Lowham's discussion here

[john.h...@gmail.com]

Not a USB stuck it's a wd 2tb hard drive no issues until.now backup is fully complete checked on PC it's the b2 scanning that fails 

[Peter Lowham]

Hi John,

When you checked your USB drive on a PC, the Windows 'Properties' would show a 'Folders' count of 2696, a 'Files' count of at least 41153 and a 'File Size' of about 844GB?

If that can be verified, then the backup is good and the issue is probably a bug.

Regards,

Peter

[john.h...@gmail.com]

Yes

Confirmed

[john.h...@gmail.com]

See attached 

[Peter Lowham]

Hi John,

Yes, your Export backup figures look very good, so I reckon that you are correct in assuming that this is a bug..

I'm sure that Paul will pick this up on Monday.

Regards,

Peter.

[David Heaton]

Hi Peter,

I wonder if you would allow me to pick your brains on an issue related to this thread?

John.H's figures show that he used 806GB of space on his backup device(according to Windows Properties) which took up 844GB of space on his B2(for 41000 tracks).

I made a new,clean backup over the weekend which according to Windows Properties took up 973GB of space on my backup device but uses 1020GB on my B2. This is for 52000 tracks.

John.H.'s difference in GB.s of space used is 36,mine is 47.

These figures would seem to indicate that roughly(very) the B2 needs about 10GB's more space per 10000 tracks than the backup devices.

Is that correct or am I misunderstanding something?

Yours,

Dave Heaton.

[PMB]

Hi John,

Thank you for highlighting this. I have forwarded the info to Martin B.

Paul

Brennan Support.

[john.h...@gmail.com]

Thanks Paul 

John 

[Peter Lowham]

Hi Dave,

Well, you have picked a great topic for a Monday morning! (:D

This is a story of technology companies mis-using unit abbreviations and designations which in turn leads to total confusion to those who don't know that this is the case.

In this example the unit 'GB' (Gigabyte) should be 1,000 x 1,000 x 1,000 bytes or 1,000,000,000 bytes.

However many tech companies also incorrectly use GB as 1,024 x 1,024 x 1,024 bytes or 1,073,741,824 bytes.  This larger number is 1 Gibibyte and its correct designation is 1 GiB.

This means that we need to use multiplication or division factors to convert these incorrectly designated units to one 'absolute' unit.

So in John's Windows 'Properties' the 'Size on disk' is incorrectly shown as 806GB when it should be 806GiB.  It is also shown (correctly) as 865,615,380,480 bytes (that is 806 x 1.074 approx = 865.5GB)

So, the absolute correct size on the backup disk is 865GB.

Then, if we look at John's figure taken from his B2, that is shown as 844.04Gb.  Again the unit designation is wrong, as a Gb is a Gigabit (the lower case 'b' is a bit, not a byte and there are 8 bits in 1 byte).

So looking at this B2's 844.04 figure, there is another adjustment to make before we get to a final accurate figure from the B2.

That is where the B2 picks up on the total number of Linux HDD sectors that the 'music' folder is using.

The Linux HDD sectors are reported in 1,024 byte sizes, so first off, the 844.04 figure should be shown as 844.04GiB not 844.04Gb.

Then we need to To convert this GiB figure to GB by multiplying 844.04 x 1.024 which equals 864.3GB (absolute).

So now we have an absolute B2 figure of 864.3GB and a Windows Backup figure of 865.6GB (absolute). 

There will always be small differences between these comparisons due to slightly difference disk formatting parameters between the internal HDD and the USB device, so this is normal.


Now, looking at your figure of 973GB of space on your backup device, that converts to 973 x 1.074 = 1045GB (the absolute figure).

Then looking at your B2 figure of 1020GB, that is 1020GiB which is 1020 x 1.024 = 1044.5GB (the absolute figure).

So your figures do match when they are correctly designated and converted to absolute values.

All very esoteric, but it's good that you are reconciling the various figures, as it can uncover problems within a music collection.  There are other checks that you can do, such as the 'Properties' of the 'music' folder should show the 'Folders' count should be # Artists + # Albums (from the B2 Stats window and the 'Files' count should be a minimum of the total # of tracks.

Regards,

Peter.

[David Heaton]

WOW,Thank you Peter for all of that amazing information(which I have to admit is completely and utterly over my head)and sorry for taking up so much of your time(Mondays or any other!)

I was curious because after I'd finished my backup,I noticed the discrepancy and was troubled that something had gone amiss even though the figure for folders(Artists plus Albums) was spot on.Then I saw the figures for John.H broadly correlated with mine and realised that my backup was,therefore hopefully, not comprised.

This is the third time that you have provided invaluable advice and support to me(a technological novice)in recent weeks and I am really very grateful,

Yours,

Dave.