You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

rebuilding thumbnail cache

We get the message to "rebuild thumbnail cache" quite often. How often is normal?

iBook G4, Mac OS X (10.4.10)

Posted on Dec 12, 2007 7:15 PM

Reply
4 replies

Dec 13, 2007 8:31 AM in response to redsoxflynn

denny, funny, i just posted this question yesterday also, however in Imovie by mistake. I copied my question and answer.....Not sure if it will help us or not..

here it goes -
When opening iphoto, sometimes i get this message "for best performance rebuild your thumbnail cache". Does anyone know what it means? i read that a couple people clicked on "rebuild now" instead of "later" and they lost all their photos....yikes!! any info is appreciated!!!
imac Mac OS X (10.4.9)

Rich839
Posts: 421
Registered: May 31, 2007
Re: rebuild thumbnail cache?
Posted: Dec 12, 2007 7:08 PM in response to: redsoxflynn
Reply Email

They probably didn't lose their photos. Their photos are located in User/Pictures/iphoto library/originals. The thumbnails are only the small pics that are displayed in the iPhoto library pane. But, if they had data base corruption of some sort, that possibly could result in loss of photos. Or if there were a power outage or interruption while the thumbnail cache was being rebuilt.

It is always advisable to back up your iPhoto library before doing any sort of rebuild. And beforehand make a copy of your Library6.iPhoto file located in your iPhoto library file in case there is data base corruption. That having been said, I have rebuilt my iPhoto library lots of times with no problem. You might want to post your concern in the iPhoto forum.

Feb 13, 2008 12:24 PM in response to dennycrane321

I too, frequently get this message "for best results Rebuild your thumbnail cache" then two options "Later" or "Rebuild now", I have on occasion, clicked both of these buttons, and have never had any noticeable change from before doing either action.

For the life of me I can NOT figure out what "triggers" this event upon launching iPhoto. When I have added new photos, it seems appropriate that the "thumbnail cache" might need to be rebuilt, so I more or less anticipate it, but it seems to come on at the most inopportune times and when I specifically want to do this action, I can't find a way to "force" this action.

Can anyone let us know what this action does, if it should be done on a regular basis, or if this is something to be more or less - Ignored?

I have searched the help archives and not been able to find even a reference to "Rebuild" and/or "Thumbnail cache" anywhere.

Feb 13, 2008 12:54 PM in response to Davebear

Davebear

Welcome to the Apple Discussions.

Like almost every app, iPhoto keeps a cache of frequently accessed data to speed up the application.

On launch, that cache is checked and if the app finds something awry then it gives out the message. I get it maybe once or twice a year - and those occasions seem to be related to when I have made big changes: a lot of deletions, for instance, or moving files between Rolls (or Events on v7).

Of course, sometimes it just happens...

I would be somewhat concerned that you are getting the message frequently. This could be a sign that your database is in trouble, or that your HD is in trouble. How big is your HD and how much free space on it?

Either way I would be very thorough about backing up.

To "force" the action: hold down the apple and option (or alt) keys when launching iPhoto...

Regards

TD

rebuilding thumbnail cache

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.