mdworker32 crashes!!!

[Xairbusdriver]

Late last week, I started getting crash dialogs concerning "mdworker32" crashes. I'd simply click the "OK" button, assuming Apple was being notified and move on. By Monday (Oct. 1, 2012), the crashing had gone berserk, to use a technical term. I could barely use the Mac because of the multiple apperances of the crash reports! I also noticed that Time Machine was stalling! Something had to be done!

I usually don't read those crash reports too closely, 95% of it is pretty much greek to me with octal numbers indicating memory locations and terms that I don't often use in conversations with friends and family. But I finally noticed that these reports had basically exactly the same info in that other 5% of the report. Specifically, there were several lines in the beginning of the report with actual English sentences and labels (well, close enough to sentences that even I could read and understand them! )!

The common thread of the reports was that the culprit was a particular item. And the exact path to that item was displayed for my amusement!

If you run Activity Monitor, you'll likely see references to "mdworker" and possibly "mdworker32" especially if you are using a pre-Lion OS. These are processes used by Spotlight (a process called "mds" specifically) which, as you know, can sometimes run amuck, to use another technical term. Apparently, Time Machine also uses "mds" or at least "mdworker" (and "mdworker32").

While in AM, I could see that "mdworker32", while it was running between crashes, was using 100% (and actually slightly more!) of one cpu! At a certain percentage, the OS would just 'kill' the runaway process in a futile attempt to save itself from total chaos! Going back to the crash report, I used the path to find the item that the OS thought was the source of the problem and probably the excessive cpu usage. It was actually a "mdimporter" file in MarinerWrite. he path shows how it and Spotlight are related: MarinerWrite.app/Contents/Library/WriteImporter.mdimporter It's that "md" part that indicates, to me, that this is additionally related to Spotlight and Time Machine.

I compressed the file, deleted the original, shutdown and restarted. I haven't had another crash, of any kind, since then! I emailed Mariner Software about the problem and my 'fix' and asked if it is in any way related to an earlier problem I have with MarinerWrite. Haven't heard back from them yet. A little searching will find many other reports of problems caused by "mdimporter" files in other apps, mostly in MS Office. I still don't know what purpose the file serve in this word processor, but I don't use it much anyway.

Lesson learned: Read the top several lines of any crash report. There just may be some useful info up there pointing to a specific file in a specific path that may easily fix your crashes. The problem is that I usually get so few crashes, I forget how the reports might actually help!

I assume/suspect that the difference between "mdworker" and "mdworker32" is that the former is a 64-bit process and the latter is a 32-bit one. AM can display a "Kind" column but all it displays on my rather recent iMac is "Intel" or "Intel (64 bit)" If you have something that can run Leopard (and thus, Rosetta), you may also see something indicating "PPC" assuming AM back then had the "Kind" abilities.

[Xairbusdriver]

Here are the pertinent parts of the Crash Report that finally led to a fix.

Frankly, I was seriously afraid that I might have to give up MaxMenus which I've been using for at least 7 years! Well before I ever had an intel Mac! I did, finally, remove a pref panel that always needed to restart when it was selected. I'm pretty sure it was a 32-bit panel.

The other problem I mentioned with Mariner Write was a failure to use the Apple supplied American Typewriter font. After an update to MW some months ago, I opened a file that I update weekly and saw the infamous blank boxes substituted for every character on the page! Any other font worked splendidly, just not that single font. Of course that font works fine in every other app that can normally select different fonts. MW techs say they are aware of the problem and working with Apple. I just switched to Pages... Saving the file as a RTF-Word shows up correctly, even with QuickLook! The font is there in the file and displays fine, even with Core Services.

[tacit]

The mdimporter is a Spotlight plugin. When people create applications that write data in formats that Spotlight doesn't know, Spotlight's search by content won't work with those documents. So the programmers can create Spotlight importers that allow Spotlight to search by content in those files.

If an importer is written incorrectly it can cause problems.

However, there is another possibility as well. Because Spotlight continuously scans the hard disk looking for things to index, it is often an early warning sign of hard disk trouble--either directory trouble or bad blocks on the disk surface. Especially if Spotlight starts using 100% CPU time and then locks up. That will happen if Spotlight is trying to index a file that is living on a bad block on the disk--Spotlight will keep blindly trying to read the bad block over and over and over again, until it pins the CPU at 100% and then OS X forces it to quit.

So there are two possibilities. One is that the Mariner Write importer has some sort of bug in it. But the other possibility is that you have developed a bad sector on your hard disk, and there is a MarinerWrite document living on that bad sector.

What I do whenever I see Spotlight behaving this way is I run Disk Utility and tell it to repair the disk. If that shows no problems, I make a backup of the disk with Carbon Copy Cloner, then reformat the disk using the zero all sectors option. (This takes a very long time; it's the sort of thing I recommend doing before you go to bed.) That will help determine whether or not a bad sector is the cause of Spotlight's meltdown. If the format fails or shows bad blocks, it's time to think about replacing the disk.

[Highmac]

Tacit, I do appreciate when someone gives some definition of a "long time". So often a message window will say an operation "may take some time" and, more often than not, it's done in a few minutes. While we all know it depends on the machine spec or internet connection, it's good to have an indication which a human can relate to. Garmin satnav map update says it may take some time. It takes about eight hours for me.

So

[Xairbusdriver]

I'm more inclined to believe the problem is with the MarinerWrite mdimporter plugin. Removing it returned everything back to normal. Several other apps have had problems with their own versions of an mdimporter plugin.

Am I correct in assuming that the mdworker32 is a 32-bit version of mdworker?

I may try to find a version that might be in the Time Machine backups. But I'm not sure one can look inside a package while inside TM. But I could restore the whole app from before it's last update...

If this "bad block" behavior is a consequence of Spotlight, I will take back my opinion that Spotlight is next to useless! At least in Mountain Lion, it doesn't waste Menu Bar space.