Here is EtreCheck's picture. It took a very long time to load and run it.
Apple's hardware diagnostic comes up with no problems.
EtreCheck version: 2.9.12 (265)
Report generated 2016-04-30 10:40:26
Download EtreCheck from https://etrecheck.com
Runtime 5:06
Performance: Below Average
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Click the [Details] links for more information about that line.
Problem: Computer is too slow
Hardware Information: ⓘ
MacBook Pro (13-inch, Mid 2012)
[Technical Specifications] - [User Guide] - [Warranty & Service]
MacBook Pro - model: MacBookPro9,2
1 2.5 GHz Intel Core i5 CPU: 2-core
4 GB RAM
BANK 0/DIMM0
2 GB DDR3 1600 MHz ok
BANK 1/DIMM0
2 GB DDR3 1600 MHz ok
Bluetooth: Good - Handoff/Airdrop2 supported
Wireless: en1: 802.11 a/b/g/n
Battery: Health = Normal - Cycle count = 663
Video Information: ⓘ
Intel HD Graphics 4000 - VRAM: 512 MB
Color LCD 1280 x 800
System Software: ⓘ
OS X Mountain Lion 10.8.5 (12F45) - Time since boot: about 3 hours
Disk Information: ⓘ
OWC Mercury Electra 6G SSD disk0 : (480.1 GB) (Solid State - TRIM: No)
disk0s1 (disk0s1) <not mounted> : 210 MB
MacBook SSD (disk0s2) / : 479.24 GB (468.07 GB free)
Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB
MATSHITADVD-R UJ-8A8 ()
USB Information: ⓘ
Microsoft Microsoft® 2.4GHz Transceiver V2.0
Apple Inc. FaceTime HD Camera (Built-in)
Apple Computer, Inc. IR Receiver
Apple Inc. BRCM20702 Hub
Apple Inc. Bluetooth USB Host Controller
Apple Inc. Apple Internal Keyboard / Trackpad
Thunderbolt Information: ⓘ
Apple Inc. thunderbolt_bus
Gatekeeper: ⓘ
Mac App Store and identified developers
System Launch Agents: ⓘ
[not loaded] 3 Apple tasks
[loaded] 119 Apple tasks
[running] 20 Apple tasks
System Launch Daemons: ⓘ
[not loaded] 58 Apple tasks
[loaded] 133 Apple tasks
[running] 42 Apple tasks
Other Apps: ⓘ
[running] [0x0-0x48048].com.etresoft.EtreCheck
[loaded] 348 Apple tasks
[running] 97 Apple tasks
Internet Plug-ins: ⓘ
QuickTime Plugin: 7.7.1 (2016-04-30)
JavaAppletPlugin: 14.6.0 - SDK 10.8 (2016-04-30) Check version
3rd Party Preference Panes: ⓘ
None
Time Machine: ⓘ
Time Machine not configured!
Top Processes by CPU: ⓘ
9% mds
8% mdworker(4)
6% fontd
4% WindowServer
1% Dock
Top Processes by Memory: ⓘ
225 MB helpd
131 MB WebProcess
115 MB Safari
82 MB mds
37 MB WindowServer
Virtual Memory Information: ⓘ
1.89 GB Free RAM
2.11 GB Used RAM
0 B Swap Used
Diagnostics Information: ⓘ
Apr 30, 2016, 07:11:00 AM Self test - passed