Console Errors from Time Machine

Question

Level 1

9 points

Console Errors from Time Machine

Time Machine starts normally, but soon gets stuck. No progress backing up, and the time estimate steadily increases. The console logs repeat this message every 15 seconds:

5/29/12 11:13:20.000 PM kernel: /SourceCache/AppleFSCompression/AppleFSCompression-37/Compressors/Dataless/comp ressorType5Kext.c:532: Error: post_request error for /Volumes/T3/Backups.backupdb/jbenniMac/2012-05-29-210005.inProgress/E793898E-8F 38-47F2-B008-060D9D5B7DDF/Macintosh HD/.DocumentRevisions-V100-bad-1/PerUID/501/153/com.apple.documentVersions/44B0 661A-E51B-4F0F-9F77-281DAF310C78.m: 35

The source drive Verifies as clean under Disk Utils. The dest drive is a new Seagate 3T goflex desk, using FW800 (also tried USB). It's freshly partitioned and formatted HFS+journaled.

Can anyone shed some light on the problem and solution, or a troubleshooting methodology?

Thanks in advance

iMac, Mac OS X (10.7.4)

Posted on May 29, 2012 8:50 PM

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Answer 1

RRFS

Level 5

4,522 points

May 29, 2012 9:10 PM in response to JBenni

This thread about says it all.

https://discussions.apple.com/thread/2748782?tstart=0

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Answer 2

JBenni Author

Level 1

9 points

May 30, 2012 5:50 AM in response to RRFS

Thanks for the link, RRFS. It says a lot, but not what I'm looking for.

That's a long thread with mixed advice and murky conclusions. Many people suggest not using Seagate drives. Others say their drives are working perfectly after removing Seagate sleep software. Still others say the issue is USB3. I had seen similar threads, and I don't think those relate to my problems.

I'm using FW800, not USB3. I have no Seagate installed files (no kexts, hidden and/or system files). My drive handles long operations without going to sleep. It runs fine from the finder, Disk Utils, and everywhere except TimeMachine. Hence, I really don't think it's any of the problems addressed in that thread. Agree?

I'd really like to know what's behind the "comp ressorType5Kext.c" error. I get no hits on searching for that text and it looks pretty funky.

Is there some file compression issue? Could I simply exclude some file from backup? Which one?

What is this message trying to tell?

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Answer 3

rkaufmann87

Level 10

149,376 points

May 30, 2012 5:57 AM in response to JBenni

If you haven't been exposed to Pondini's Time Machine Troubleshooting & Time Machine FAQs you will probably find your answer there.

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Answer 4

JBenni Author

Level 1

9 points

May 30, 2012 6:08 AM in response to rkaufmann87

Been there, done that. That's how I located the alarming console messages.

I'm really looking for help understanding the console message. I learned that snow leopard has a new HFS+ file compression feature and the problem I'm having does appear to be related to compression (based on the message text).

Can anyone help identify the cause of the console message:

5/30/12 9:03:28.000 AM kernel: /SourceCache/AppleFSCompression/AppleFSCompression-37/Compressors/Dataless/comp ressorType5Kext.c:532: Error: post_request error for /Volumes/T3/Backups.backupdb/jbenniMac/2012-05-30-084212.inProgress/1C6092BC-15 44-4B25-97EC-CAF382604372/Macintosh HD/.DocumentRevisions-V100-bad-1/PerUID/501/118/com.apple.documentVersions/10AF D71C-1C15-426A-8156-DD957ADD2A45.m: 35

That's got to be trying to say something.

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Answer 5

JBenni Author

Level 1

9 points

May 30, 2012 6:58 AM in response to JBenni

One more bit of console message that I didn't realize was related:

5/30/12 9:54:11.000 AM kernel: decmpfs.c:1309:decmpfs_read_compressed: decmpfs_fetch_uncompressed_data err -35

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Answer 6

Pondini

Level 8

38,883 points

May 30, 2012 5:50 PM in response to JBenni

JBenni wrote:

. . .

5/29/12 11:13:20.000 PM kernel: /SourceCache/AppleFSCompression/AppleFSCompression-37/Compressors/Dataless/comp ressorType5Kext.c:532: Error: post_request error for /Volumes/T3/Backups.backupdb/jbenniMac/2012-05-29-210005.inProgress/E793898E-8F 38-47F2-B008-060D9D5B7DDF/Macintosh HD/.DocumentRevisions-V100-bad-1/PerUID/501/153/com.apple.documentVersions/44B0 661A-E51B-4F0F-9F77-281DAF310C78.m: 35

I'm not sure what that's all about, but what jumps at me is /.DocumentRevisions-V101-bad-1

.DocumentRevisions-V101 is your (hidden) Versions database (all the previously-changed "chunks" of files made by apps that support AutoSave and Versions).

Seeing -bad-1 appended to the name looks like the database got corrupted internally (in a way Disk Utility can't detect), OSX renamed it, and made a new one.

First, let's exclude that from Time Machine backups (ironically, the "good" version is excluded automatically!). See Time Machine - Frequently Asked Question #10 -- you'll have to check the Show Invisible Items box there, then on your internal HD, you should see the "bad" folder you want to exclude.

Then run a backup and report your results.

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Answer 7

JBenni Author

Level 1

9 points

May 31, 2012 3:49 AM in response to Pondini

Brilliant! Thank you Pondini - you rock!

I excluded that directory for TM and now it appears to be running normally. It's already past the point where the hang had previously occurred. (Because it's a first backup to this disk, it will take a while.)

In retrospect, I don't think I saw that the file path on the destination volume (T3) reflected the source path. The path looked pretty alien and I didn't recognize that it reflected the source file path.

I'm grateful that you did, and you knew what that directory was about, and took the time to respond. (BTW, I had previously encountered some funk in the Preview App with saving Versions. But it wasn't fatal and I had forgotten about it. It might explain why the Versions DB was marked bad and rebuilt.) I'm not sure why the bad DocumentRevisions directory was included in TM, but I have no qualms about excluding it.

Anyway, I'm very optimistic that your advice provided a full fix and will confirm as soon as it runs to completion. I'm incredibly grateful for the excellent assist. Thank you!

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Answer 8

Pondini

Level 8

38,883 points

May 31, 2012 7:59 AM in response to JBenni

JBenni wrote:

. . .

(BTW, I had previously encountered some funk in the Preview App with saving Versions. But it wasn't fatal and I had forgotten about it. It might explain why the Versions DB was marked bad and rebuilt.)

Yup, sure sounds like it. You've lost all previous versions (of all files changed by apps that support AutoSave and Versions).

I'm not sure why the bad DocumentRevisions directory was included in TM, but I have no qualms about excluding it.

Time Machine backs-up everything by default, except for some specific things it excludes automatically, such as system work files, trash, most caches and logs, and, on Lion, the Local Snapshots (laptops) and Versions databases. Since the damaged one has a different name, it got included accidentally.

Anyway, I'm very optimistic that your advice provided a full fix and will confirm as soon as it runs to completion.

Great!

Then, you'll want to delete the culprit entirely (it's usually best to just exclude first, to confirm that's really the problem, and see if anything else is wrong.)

Message was edited by: Pondini

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Answer 9

JBenni Author

Level 1

9 points

May 31, 2012 10:39 AM in response to JBenni

Success. I'm really grateful to have TM working.

I'll delete the offending directory and get on with life.

I can't thank you enough!

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Answer 10

Pondini

Level 8

38,883 points

May 31, 2012 11:07 AM in response to JBenni

JBenni wrote:

Success. I'm really grateful to have TM working.

Yay! 🙂

I'll delete the offending directory and get on with life.

You'll need to be able to make hidden items visible. If you don't know how, use the TinkerTool app, per #A3 of Time Machine - Troubleshooting. And you'll have to authenticate with your Admin password, of course.

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