Add more RAM or cut back on the number of concurrently running applications and utilities.Please see the following from the user, fotomac: "The solution was to SIGN OUT of iCloud and my problem STOPPED! NO MORE SPINNING BEACHBALL! My computer's speed increased to what it should be and all my Apps now work!" It can slow down the computer considerably. If you have enabled iCloud Disk and are storing your Documents and Data in iCloud, then consider turning that off and signing out of iCloud.Doing so means you must maintain regular and multiple backups.
Experienced users erase the hard drive and do a clean install from scratch from time to time or whenever installing a major OS upgrade. All computers become slower over time even under normal use. Usually, this software does more bad than good. Avoid using any third-party cleanup software.Tips to Fix Issues that affect Mac Performance.Visit The XLab FAQs and read the FAQ on Performance.OS X El Capitan- If your Mac runs slowly.6 Easy Tips to Speed Up OS X Yosemite on Your Mac.
How to fix slow shutdown and startup times.Fix slow start-ups in OS X | MacFixIt - CNET Reviews.Slow Mac Performance? This Article Solves It!.17 Reasons Why Your Mac Runs Slower Than it Should.Select Reinstall OS X and click on the Continue button.Quit Disk Utility and return to the Utility Menu.Click on the Apply button, then wait for the Done button to activate and click on it.
Set the Format type to Mac OS Extended (Journaled.).Click on the Erase icon in Disk Utility's toolbar.When Disk Utility loads select the drive (out-dented entry) from the Device list.
Quit Disk Utility and return to the Utility Menu. Click on the First Aid button in the toolbar. Select the indented (usually, Macintosh HD) volume entry from the side list. Choose Disk Utility and click on the Continue button. Immediately after the chime hold down the Command and R keys until the Utility Menu appears.