Lion mdworker and mdworker32 draining battery

I was having a similar problem with mds hogging resources, often taking 100% of one core out of 4.

I tried various things including excluing some partitions from spotlight and repairing permissions on all my disks and nothing work.

Then last night I ran software update which took me to 10.7.4 and today at least mds is behaving - not taking much resource at all.

I just thought I'd throw in the data point -- This is a 27 inch mid 2010 iMac. I'm running Lion 10.7.4 and STILL periodically have this problem re-occur -- high disk-I/O and high network I/O when the system is othewise simply sitting there doing nothing. (High I/O rates mean "more than zero" -- when the system is sitting there otherwise quiescent.)

Looking at Activity monitor, MDS and/or MDworker is eating up 20-40% of the CPU.

In my case it is particularly noticable because my internal HD is noisy -- Makes it easy to tell when it is getting a workout.

These periods of activity will last 10-20 minutes at random intervals. One will usually kick off shortly after any time I log in. (I always logout of my account overnight and don't automatically re-open windows -- letting stickies run as a logon process.)

This situation has been happening since I upgraded to Lion last fall.

Hmm. Some cpu spikes by MDS and MDWorker are normal, usually after creating a large number of new files (or even one very large one), which can happen at startup even wthout automatically re-opening windows, and especially if more than 8 hours has passed. There are periodic system maintenance events that run daily/weekly/monthly that can trip it. One thing you might check is if you have some kind of repeating system error. Log in to an admin account and bring up the Console app. If you see repeated error messages, it could mean that something is out of whack and MDS is repeatedly re-indexing something, or trying to. 10-20 minutes is a pretty long time for periodic stuff.

Not only does this process (whatever it is) take much longer than expected, but the Console log is FULL of MD/MDworker errors related to each run ...

LOTS (pages) of this type:

com.apple.mdworker.isolation.0: invalid stream length 4843; should be 4725.

Interspersed with:

com.apple.mdworker.isolation.0: *** process 95258 exceeded 500 log message per second limit - remaining messages this second discarded ***

com.apple.mdworker.isolation.0: LZW decode: invalid chain sequence.

com.apple.mdworker.isolation.0: invalid stream length 2141; should be 2139.

com.apple.mdworker.isolation.0: LZW decode: encountered unexpected EOF.

Just to pick a few of the more common ones -- but only when you only look at teh "All Messages" log, never any in the "DIagnostic and User Messages."

====

Interestingly, since posting about this yesterday, I was reading an Apple Tech note, primarily about ixxx and photos, with Lion etc. (I sync an iPhone and iPad with this iMac)

Since I have "integrated" multiple different Macs with this one over the years by dragging stuff from them to here, I figured, what the heck, I probably have all kinds of reandom ownerships/groups so I did the "get-info home/apply to enclosed" thing, and so far since I did that last evening, I have not had mdworker kick off again! I realize that this was less than 24 hours ago at this point in time, but I was seeing this issue much more frequently than that.

====

Now if the "disppearing WiFi problem on 27 inch iMacs" also goes away !!!

SHAME APPLE that you seem to want some stupid WINDOWS solution to an actual problem! I had had this link with the actual solution a week ago, but you seem to want some stupid '500 clicks' solution' that would make this cool for windows users. KNOW YOUR AUDIENCE. The mac solution is ulike anyting for 'winders', stop acting like it is. Please post the actual solution to the problem per the original post, or else you are just another Jobs-problem, and we are just stuck in a Windows world.

I tried so many things to solve my mdworker exhuberence and it's running every 30 minutes or so at 100% like a busy lil' beaver and draining my battery. I looked at many different things that might be changing my file system regularly. I turned off time machine, stopped various jobs, etc. Then I saw a post on a large inbox causing problems and it clicked! The inbox changes every time there is mail delivered. If it is large it can cause the mdworker process to work overtime trying to reindex it every time it changes. I cleaned my inbox and archived my mail I wanted to keep to another folder. Now I have about 2000 msgs in the inbox. I also turned off spotlight searches of my mail. Now my machine is much more docile and the fan is off most the time. This has been so for only a few hours, so I'm still waiting on the final verdict. I think its a score for I have been dealing with this for months. So if you have a very large inbox, 1000s of messages, you may try moving mail so that the inbox in smaller and see if those lil' mdworkers get a rest at last.