kernel_task too high?

Hi All -- after getting some adware, I've been cleaning up my laptop. Seems under control except kernel_task memory use seems high. Should I do anything about it, or is it within normal operating range? If too high, what do I do? Thanks much

Problem description:

kernel_task

EtreCheck version: 2.2 (132)

Report generated 4/28/15, 12:14 PM

Download EtreCheck from http://etresoft.com/etrecheck

Click the [Click for support] links for help with non-Apple products.

Click the [Click for details] links for more information about that line.

Hardware Information: ℹ️

MacBook Pro (Retina, 13-inch, Late 2013) (Technical Specifications)

MacBook Pro - model: MacBookPro11,1

1 2.4 GHz Intel Core i5 CPU: 2-core

8 GB RAM Not upgradeable

BANK 0/DIMM0

4 GB DDR3 1600 MHz ok

BANK 1/DIMM0

4 GB DDR3 1600 MHz ok

Bluetooth: Good - Handoff/Airdrop2 supported

Wireless: en0: 802.11 a/b/g/n/ac

Battery: Health = Normal - Cycle count = 81 - SN = D86336701A9FC1752

Video Information: ℹ️

Intel Iris

Color LCD 2560 x 1600

System Software: ℹ️

OS X 10.10.3 (14D136) - Time since boot: 2:48:45

Disk Information: ℹ️

APPLE SSD SM0256F disk0 : (251 GB)

EFI (disk0s1) <not mounted> : 210 MB

Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB

Macintosh HD (disk1) / : 249.77 GB (148.68 GB free)

Core Storage: disk0s2 250.14 GB Online

USB Information: ℹ️

Apple Internal Memory Card Reader

Apple Inc. BRCM20702 Hub

Apple Inc. Bluetooth USB Host Controller

Apple Inc. Apple Internal Keyboard / Trackpad

Thunderbolt Information: ℹ️

Apple Inc. thunderbolt_bus

Gatekeeper: ℹ️

Mac App Store and identified developers

Launch Agents: ℹ️

[loaded] com.oracle.java.Java-Updater.plist [Click for support]

Launch Daemons: ℹ️

[loaded] com.oracle.java.Helper-Tool.plist [Click for support]

[loaded] com.oracle.java.JavaUpdateHelper.plist [Click for support]

User Login Items: ℹ️

None

Internet Plug-ins: ℹ️

Silverlight: Version: 5.1.30514.0 - SDK 10.6 [Click for support]

Flip4Mac WMV Plugin: Version: 3.2.0.16 - SDK 10.8 [Click for support]

QuickTime Plugin: Version: 7.7.3

JavaAppletPlugin: Version: Java 8 Update 45 Check version

Default Browser: Version: 600 - SDK 10.10

3rd Party Preference Panes: ℹ️

Flip4Mac WMV [Click for support]

Java [Click for support]

Time Machine: ℹ️

Time Machine not configured!

Top Processes by CPU: ℹ️

5% WindowServer

4% fontd

0% taskgated

0% notifyd

0% cloudpaird

Top Processes by Memory: ℹ️

571 MB kernel_task

205 MB com.apple.WebKit.WebContent(3)

164 MB Finder

156 MB Mail

147 MB mds_stores

Virtual Memory Information: ℹ️

2.23 GB Free RAM

5.77 GB Used RAM

0 B Swap Used

Diagnostics Information: ℹ️

Apr 28, 2015, 09:25:37 AM Self test - passed

Apr 28, 2015, 08:56:52 AM /Library/Logs/DiagnosticReports/SophosSXLD_2015-04-28-085652_[redacted].cpu_res ource.diag [Click for details]

Apr 28, 2015, 08:34:04 AM /Library/Logs/DiagnosticReports/SophosAVAgent_2015-04-28-083404_[redacted].cras h