I'm new to Macintosh. My wife has had a Mac with Snow Leopard 10.6.3 for about two years. We leave it running continually. In just the past two months it has been sluggish when we come back to it after it has been idle for a long time. I went to http://support.apple.com/kb/ts1417 and tried a safe boot according to the instructions there. It didn't seem to help. I then used the disk utility repair function and that made the situation better (no longer freezing up and needing a slow and sluggish reboot after idle), but still didn't solve the problem.
Here are some things to check that might lead you (or us) to the answer:
- When did this issue being? Did it accompany any significant hardware or software changes to the system that you can remember?
- Snow Leopard hasn't been available for two years so your OS must have been upgraded since you've owned the machine. Did you do the upgrade, and do you remember it being anything other than a totally routine installation?
- Have you added or removed any hardware, like an external disk, that some process used to use and may now be futilely searching for?
- Run Activity Monitor (in the Applications/Utilities folder) and look for anything that seems unusually active: CPU, network, or disk activity. Can you correlate it with any processes in the process list?
- Run Console (also in the Utilities folder) right after you wake or boot the system and look for any suspicious error messages or anything dumping the same message repeatedly into the log.
- Check your disk's free space - you want more than 10% or 15% free (Activity Monitor again, Disk Usage tab).
Any more information you can add (edit your question) will help
In the Energy Saver System Preferences pane, try unchecking 'Put Hard Disks to Sleep when Possible'.
If your "sluggish" sensation is coming from the spinning beach ball, install XCode tools and leave the 'SpinControl' application running as it'll record capture data about which apps are hanging and for how long.
Whenever OS X feels a bit sluggish, I try cleaning up the system and repairing the directory structure.
If you haven't done so, try using OnyX. It's one of the best known disk cleanup and system maintenance tools and it's free.
Also uninstall unused applications. Even though uninstalling on a Mac is as simple as dragging the application to the trash, it leaves behind a trail of preference and setting files on the disk which pile up on the system. There are free tools available which will automatically delete those "related" files when you trash an application. Two of these are: AppTrap and TrashMe. I've found TrashMe to perform better at many instances.