Figuring out your computer’s ‘cache’ advance

FI-Log-On-With-Larry-SchneiderDear Larry,

I’ve been told that it’s a good thing to restart my computer at least once a day. But I find that after I restart, my computer actually seems to run slower than usual. What’s up with that?

F. C.

Dear F. C.,

Computers can go days without a reboot, but when they do restart, it’s still like a comforting shower, a morning wake-up call if you will, that cleans out the pipes and gets the computer ready for a bright new day.

But you’re right. For a period of time following the reboot, your computer actually runs slower than what you’re accustomed to. That first click on America Online or Microsoft Word following a restart seems to require an inordinate amount of time before the program starts up and is ready for use. Yet if you close it and reopen it, it starts up lickety-split. So what’s going on here?

As you know, your computer’s hard drive is used for long term storage — sort of like your filing cabinet — and the computer’s memory is akin to the top of your desk where the work actually takes place. When you need to work on a particular project, you retrieve its folder from your filing cabinet and open it on your desk. As you need to work on other projects, other files are recovered from the filing cabinet.

The bigger your desk — i.e., the more memory your computer has — the faster and more efficient your work.

As your desk gets overcrowded, you have to start putting files back in the filing cabinet to make room, and all that extra effort slows you down. It’s the same with your computer. A restart clears the computer’s memory the same as if you cleared off your desk at the end of a long day.

So, when you turn it on the next morning, your computer has to retrieve programs and files from the hard drive in the same way you have to go back to your filing cabinet to start the day’s work. It’s this initial startup that you’re perceiving as your computer running slower than usual.

Your computer’s memory is significantly faster than the hard drive. Moreover, your computer has special memory assigned to it, memory that’s even faster (and more expensive) than regular memory. Your computer uses this speedy memory to cache (pronounced “cash”) data retrieved from the slower memory and the even slower hard drive.

A cache is like a smart librarian. When a patron asks for a Harry Potter book, the librarian goes looking for it on the shelves (i.e., the hard drive) and comes back with it along with the other Harry Potter books that were filed around it. This material is kept in a special place behind the desk (cache memory) so that when other patrons ask for a Harry Potter book, the librarian can retrieve it much more quickly. It’s an efficient system indeed.

This is Larry Schneider, logging off.


Larry Schneider is the owner of Accent on Computers, a Greenwich-based consulting firm — now in its 15th year of business — catering to individuals, businesses and professional offices. PC and Mac services include computer setup, training, troubleshooting, virus resolution, networking, Internet, database, and programming. Call 203-625-7575, visit or send email to [email protected]

By participating in the comments section of this site you are agreeing to our Privacy Policy and User Agreement

© Hersam Acorn. All rights reserved. The Greenwich Post, 10 Corbin Drive, Floor 3, Darien, CT 06820

Designed by WPSHOWER

Powered by WordPress