iMac is slow, memory pressure green

Question

I really need help with this one. It's extremely important, I can't afford to buy a new computer. So maybe like 3 or 4 weeks ago I got a virus. We got rid of the virus, but the computer was sill INCREDIBLY slow. It got so extreme I had to wipe the drive and install a fresh copy of macOS Sierra. This still did not make it faster. It sure helped, but it didn't fix it. I have to do frequent restarts to get mild preformance for like 10 minutes. As of time of writing, it's being very slow. I'm barely able to type.

So I asked on StackExchange, but I didn't pose my question correct I guess, so at the end, the answer was, I do not need more RAM. I want to fix my computer all the way and make it fast like it was before the virus. I ran like every command on the internet and an EtreCheck to make sure that I have all the information any of you will probably need, if I don't, I'll gladly run any diagnostic.

Apple Hardware Test: Passed

SMART Status: Verified

EtreCheck Log: http://pastebin.com/KN4Ad1hS

Terminal Commands: http://pastebin.com/Gyjm6keX (sorry it wouldn't let me post more than 2 links, so I put the 2 command's pastebin links in one pastebin)

diskutil list:

/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            999.3 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3

diskutil verifyDisk disk0:

Started partition map verification on disk0
Checking prerequisites
Checking the partition list
Checking the partition map size
Checking for an EFI system partition
Checking the EFI system partition's size
Checking the EFI system partition's file system
Checking the EFI system partition's folder content
Checking all HFS data partition loader spaces
Checking booter partitions
Checking booter partition disk0s3
Verifying file system
Checking Journaled HFS Plus volume
Checking extents overflow file
Checking catalog file
Checking multi-linked files
Checking catalog hierarchy
Checking extended attributes file
Checking volume bitmap
Checking volume information
The volume Recovery HD appears to be OK
File system check exit code is 0
Checking Core Storage Physical Volume partitions
The partition map appears to be OK
Finished partition map verification on disk0

Computer Info Image:

Activity Monitor Image:

Please help! Thanks :)!

Answer 1

I remember your other questions, so will try and help you get to the bottom of this. You need to understand though, that troubleshooting is a process of elimination and, as a result, can take some time.

Before we start, I am going to ignore that you had a virus a few weeks ago, because that could be confusing things. In other words, we need to start afresh because the virus and this issue may be totally unrelated.

I can see from the various images you posted that you do have plenty of free hard drive space, so that's one possible cause we can eliminate. So, one by one, let's try and resolve this.

1. Let's start your computer in Safe Mode

Our first test will be to see what happens when you start your iMac in Safe Mode. Doing this forces your iMac to perform some tests and also prevents some software from automatically loading or opening.

Follow these steps:

• Shutdown your iMac
• As soon as you hear the startup sound, press and hold the Shift key
• Once you see the Apple logo, let go of the Shift key

Don't be concerned if your iMac takes longer to boot up (remember it's performing some tests). After it's booted, use it for a while. Do this for long enough for you to be satisfied that the problem still persists (or not). Once you're done, restart the computer normally to exit Safe Mode.

Note: While in Safe mode you won't be able to do everything you normally can, and your macOS environment may appear/work differently. Do not worry about this.

When ready, report back on how you went.

2. Create and log in to a new user account

Our next test is to create a totally new user account and check whether logging in to this has any impact on performance. In case you don't know how to do this, follow these steps:

• Go to Apple Menu > System Preferences
• Select Users and Groups
• Click on the + sign at bottom left to add a new user (you may need to unlock the padlock below that to make changes)
• Set your user options and ensure that automatic login is off
• Exit System Preferences

Now restart your computer and log in to the newly created user account. Once logged in, do not install any new software etc. Instead, just use the computer for a while to determine if it is still slow.

When ready, report back on how you went.

3. Install macOS Sierra on an external drive

Our next test is to take advantage of your external hard drive to try and determine whether we have an issue between macOS Sierra and your computer. If not, it may indicate either a problem with your internal hard drive or 3rd party software.

Use this process:

• Do a full installation of macOS Sierra on the external hard drive but do not install any 3rd party software.
• Restart your Mac.
• Immediately press and hold the Option key.
• The Startup Manager will appear and shouldn't take too long to list your internal hard drive and the external drive.
• Use your mouse or the left/right arrow keys to select the external hard drive you just installed macOS Sierra on
• Double-click or press the Return key to start your iMac from the external hard drive

Now use your iMac from the external drive for a while doing a few things to get a sense of how well it's responding. Please only use default Apple apps (such as Safari etc) for now.

When ready, report back on how you went.