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TOPIC: Western Digital drive problems

Western Digital drive problems 16 Dec 2013 04:43 #5035

I have an external USB connected Western Digital My Book 2TB external drive that has a partition for Time Machine (it's bigger than my internal drive) and a couple smaller partitions. It's now exhibiting the same behavior problems that I experienced with a My Book 1TB drive last year. Which is HORRIBLE read/write speeds. So much so that I can't run a video file off the drive as it constantly stops and has to cache forward. And even small TimeMachine backups (16mb, for example) take so long that by the time it finishes it's time for another backup. Which means my machine is backing up almost all the time.

As with last time I ran TTP on the drive and it took a LONG time and no significant errors found. So far I've only checked a 400GB partition that is 25% full and it took 13 hours to clear. I'm currently 10 hours into my TimeMachine backup partition's test, but IIRC last time it went for several days and (again) found nothing significant to fix.

The reason TTP is taking so long to perform these tests is because there is a definite problem with r/w speed. So of course it's going to take TTP forever to get anything done. But why is it not finding any problems? Clearly something is wrong.

With the 1TB drive problem last year I got frustrated, bought the 2TB drive, moved everything over (which took almost a week), then wiped the 1TB drive clean with a reformat. Speed was awesome as it should be. Same with the 2TB drive for many months, but over time it got slower and slower and now I'm back to where I was before.

Any thoughts on this?

Steve


OS = 10.6.8
Model Name: MacBook Pro
Model Identifier: MacBookPro5,3
Processor Name: Intel Core 2 Duo
Processor Speed: 2.66 GHz
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L2 Cache: 3 MB
Memory: 4 GB
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Western Digital drive problems 16 Dec 2013 05:10 #5036

If the Surface Scan finds no errors (unremapped bad blocks) and the drive passes the Drives test, and there are no disk directory errors, I suggest you contact Western Digital to see if there are any known problems with your particular model, or if there is a firmware update available for it. C

onnecting a Time Machine volume via USB is bound to be slow after the Time Machine volume has many backups on it. The disk directory becomes very complex on a TIme Machine volume.

Tacit, the founder of the Fine Tuned Mad forums, once posted this comparison of USB and FIreWire in the original MacFixIt Forums:

tacit
MacGuru

Registered: 10/14/99
Posts: 11990
Loc: Portland, Oregon, USA
Without going into technical reasons, the simple answer is that FireWire uses a more efficient command set and more efficient techniques for transmitting data that rely on less overhead.

Here's a quick and crude metaphor that might help illustrate ow USB can seem to have a higher data transmission rate but actually is slower in the real world. Imagine that we have two different types of connections. We'll call them ImaginaryA and ImaginaryB. ImaginaryA and ImaginaryB both are used to connect a computer to a hard drive. They use different "protocols," or techniques for sending information back and forth.

When a computer talks to a hard drive using ImaginaryA, it goes something like this:

computer: Hard drive, please give me your unit number
hard drive: Hard drive unit number is 1102
computer: Hard drive 1102, please give me your size
hard drive: Hard drive 1102 reports that the total size for hard drive 1102 is 150 GB
computer: Hard drive 1102, please locate block number 332.
hard drive: Hard drive 1102 reports that block number 332 has been located.
computer: hard drive 1102, please give me 10 bytes of data starting at block 332.
hard drive: Beginning the read. 23. 45. 22. 12. 55. 87. 76. 32. 99. 21. Read finished. Did you get that all OK?
computer: Hard drive 1102, I got all the data OK.

Now let's say that you attach a hard drive using the ImaginaryB port on your computer and read the exact same data. The "conversation" between the computer and the hard drive looks like this:

computer: ID
hard drive: 1102
computer: 1102 size
hard drive: 150g
computer: 1102 position 332
hard drive: 332 ok
computer: 1102 read 10 332
hard drive: 23 45 22 12 55 87 76 32 99 21 ok
computer: ok

Now, even if the computer "talks" to the hard drive at the same speed using ImaginaryA and ImaginaryB, it's clear to see that the computer will read data from the hard drive using ImaginaryB much, much faster, because the commands that go back and forth are shorter and simpler.
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Western Digital drive problems 16 Dec 2013 05:26 #5037

I originally thought the first drive might have a problem, but I bought the second one and I've not seen any signs of systemic problems with these drives mentioned on the net. Plus, a reformat (last time) fixed the speed issue, so I was thinking it was directory related.

What to do about the TimeMachine directory fragmentation? I do remember last time that it found no errors, but did report that the directory was a mess. Yet I keep reading that you shouldn't optimize a TimeMachine drive. True or not?

As an aside, any way to get my user name to show up instead of my real name? I couldn't find anything in my Profile to specify which is displayed.

Thanks,

Steve
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Western Digital drive problems 16 Dec 2013 11:38 #5038

In my experience and that of many other people, Time Machine volumes eventually become corrupted. If you have 40 backups on a Time Machine volume, you have a disk directory that is 40 times as large and complex as the directory of the volume that was backed up to the Time Machine volume. Fixing such a directory takes too much RAM and too much time, as would optimizing the Time Machine volume (you would need to have a backup of the TIme Machine if you did attempt to optimize it). Starting over is a good approach. Do not rely on Time Machine to be your only backup. You should also have a clone.


You can change the user name in Account Maintenance --> Account Information --> user name.
MicroMat Inc
Makers of TechTool
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Western Digital drive problems 16 Dec 2013 16:17 #5039

OK, I'll just rebuild it then.

As for changing my display name, I don't see how that's done. I got to that screen easily enough before I asked, but there's no button, popup, or anything else there to specify what name to have displayed. Just my personal info in various field and then a section where I can fill in what product I own.

Steve
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Western Digital drive problems 16 Dec 2013 16:23 #5040

I forgot to ask a related question.

I have three partitions on the 2TB drive; TimeMachine, backup for some large art files I don't want to have subjected to TimeMachine, and a third one for dead storage. I can understand how the directory of the TimeMachine partition gets messed up. I've certainly read this before and it makes sense. But why would the performance of my other partitions drop down so low? For example, I'm backing up my art files off the 2TB drive to my 1TB drive and it says a 64GB disk image is going to take 36 hours to copy over. I haven't done the math on that, but that doesn't seem right at all.

Steve
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Western Digital drive problems 16 Dec 2013 17:17 #5041

The username field is at the upper right corner of the window you see when you choose My Account (upper right corner of this window), then click the Account Information button.

I do not know why the file copies are taking so long. I can only suggest that you contact Western Digital, and check the All Messages log (or the system and console logs) to see if any errors are being logged that appear to be related to the copying. One such error can appear as:

i/o error

or

input/output error

I suggest that you not attempt to rebuild the disk directory on the Time Machine volume. You are likely to run out of both time and RAM.

The next time you buy an external drive, try to get one that has a faster protocol, such as FireWire. USB was not intended to be used for large hard drives.
MicroMat Inc
Makers of TechTool
Last Edit: 16 Dec 2013 17:20 by micromattech3.
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Western Digital drive problems 16 Dec 2013 17:36 #5042

I guess the answer is "that's why the drives are so cheap". Dang, I hate it when they make stuff that really doesn't work in the real world.

I checked my logs and no errors. My only guess, based on my last experience, is that the volume directory is somehow impacted by a the TimeMachine partition being overloaded. Because last year I had the same exact problems and a drive reformat fixed everything. And like last time this is something that's been getting worse as time passes, yet no errors. Just loss of speed.

I dunno what's wrong with what I'm seeing in My Account. I've been to Account Maintenance -> Account Information a dozen times already. I do not see any option for switching to use my Username vs. my real name. There is already a value in the Username field, so if this Forum is coded to use that by default it's not. I checked in Firefox just to be sure it wasn't my creaky version of Safari causing a problem. Same result for both. So what am I supposed to do once I get to Account Information screen?

Thanks!

Steve
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Western Digital drive problems 16 Dec 2013 18:32 #5043

If you do not see your real name in the username field, please send a message to This email address is being protected from spambots. You need JavaScript enabled to view it. about this problem, including a link to this thread. Thank you.

I have a friend who is a professional photographer. He has 18 disk drives. His Time Machine volumes invariably become corrupted after around six months of use. If you create a file, and it gets backed up to Time Machine, and you never modify the file, your Time Machine disk directory has as many links to that file as you have backups on the Time Machine. The disk directory becomes many GB in size.
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