Mac freezes without any specific action

Hard to say exactly what's causing the freezes but if you download and run EtreCheck then post the results in your Reply that would give us an idea of might be causing the problem.

https://etrecheck.com

No personal data is shared from an EtreCheck report.

Also, right after a force quit...

Open Console in Applications>Utilities & see if there are any clues in System log from the time & date of the freeze to startup complete.

Click on the top line we want, Shift plus click on the bottom line we want, CMD+c to copy, then paste the text in a reply with CMD+v

A few dozen lines should be about right, hundreds or thousands won't likely be readable.

I have this same issue. Here is the log from the minute prior to the freeze and having to force a reboot. I'm imagining it's Safari related...

3/27/16 2:03:09.942 PM com.apple.WebKit.WebContent[888]: [14:03:09.942] FigAgglomeratorSetObjectForKey signalled err=-16020 (kFigStringConformerError_ParamErr) (NULL key) at /Library/Caches/com.apple.xbs/Sources/CoreMedia/CoreMedia-1731.15.202/Prototype s/LegibleOutput/FigAgglomerator.c line 92

3/27/16 2:03:09.944 PM com.apple.WebKit.WebContent[888]: [14:03:09.944] <<<< IQ-CA >>>> piqca_setUsePreQueue: (0x7fee42a35600) rejecting report of layer being serviced - IQ has not yet begun to update

3/27/16 2:03:13.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) ipc-posix-sem SandboxingDetectionTest

3/27/16 2:03:15.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) mach-lookup com.apple.dock.fullscreen

3/27/16 2:03:18.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) ipc-posix-sem SandboxingDetectionTest

3/27/16 2:03:27.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) mach-lookup com.apple.dock.fullscreen

3/27/16 2:03:37.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) ipc-posix-sem SandboxingDetectionTest

3/27/16 2:03:40.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) mach-lookup com.apple.dock.fullscreen

3/27/16 2:03:52.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) mach-lookup com.apple.dock.fullscreen

3/27/16 2:03:56.295 PM com.apple.WebKit.WebContent[888]: [14:03:56.295] <<<< IQ-CA >>>> piqca_setUsePreQueue: (0x7fee42a35600) rejecting report of layer being serviced - IQ has not yet begun to update

3/27/16 2:04:01.399 PM com.apple.WebKit.WebContent[888]: [14:04:01.399] <<<< Boss >>>> figPlaybackBossPrerollCompleted: unexpected preroll-complete notification

3/27/16 2:04:01.552 PM com.apple.WebKit.WebContent[888]: [14:04:01.552] FigAgglomeratorSetObjectForKey signalled err=-16020 (kFigStringConformerError_ParamErr) (NULL key) at /Library/Caches/com.apple.xbs/Sources/CoreMedia/CoreMedia-1731.15.202/Prototype s/LegibleOutput/FigAgglomerator.c line 92

3/27/16 2:04:04.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) mach-lookup com.apple.dock.fullscreen

3/27/16 2:04:04.000 PM syslogd[46]: ASL Sender Statistics

3/27/16 2:04:07.045 PM com.apple.WebKit.WebContent[888]: <<<< MediaValidator >>>> mv_ValidateRFC4281CodecId: Unrecognized codec 1.(null). Failed codec specific check.

3/27/16 2:04:07.045 PM com.apple.WebKit.WebContent[888]: <<<< MediaValidator >>>> mv_LookupCodecSupport: Unrecognized codec 1

3/27/16 2:04:07.045 PM com.apple.WebKit.WebContent[888]: [14:04:07.045] mv_LowLevelCheckIfVideoPlayableUsingDecoder signalled err=-12956 (kFigMediaValidatorError_VideoCodecNotSupported) (video codec 1) at line 1921

3/27/16 2:04:07.045 PM com.apple.WebKit.WebContent[888]: <<<< MediaValidator >>>> mv_TestCodecSupportUsingDecoders: Unrecognized codec 1

3/27/16 2:04:07.045 PM com.apple.WebKit.WebContent[888]: <<<< MediaValidator >>>> mv_ValidateRFC4281CodecId: Unrecognized codec 1.(null). Failed codec specific check.

3/27/16 2:04:07.045 PM com.apple.WebKit.WebContent[888]: <<<< MediaValidator >>>> mv_LookupCodecSupport: Unrecognized codec 1

3/27/16 2:04:07.045 PM com.apple.WebKit.WebContent[888]: [14:04:07.045] mv_LowLevelCheckIfVideoPlayableUsingDecoder signalled err=-12956 (kFigMediaValidatorError_VideoCodecNotSupported) (video codec 1) at line 1921

3/27/16 2:04:07.046 PM com.apple.WebKit.WebContent[888]: <<<< MediaValidator >>>> mv_TestCodecSupportUsingDecoders: Unrecognized codec 1

3/27/16 2:04:08.799 PM WindowServer[156]: _CGXRemoveWindowFromWindowMovementGroup: window 0x60 is not attached to window 0xd0

3/27/16 2:04:09.623 PM com.apple.WebKit.WebContent[888]: <<<< FigByteStream >>>> FigByteStreamStatsLogOneRead: ByteStream read of 8 bytes @ 23390 took 1.664273 secs. to complete, 1 reads >= 1 sec.

3/27/16 2:04:10.050 PM com.apple.WebKit.WebContent[888]: [14:04:10.049] FigAgglomeratorSetObjectForKey signalled err=-16020 (kFigStringConformerError_ParamErr) (NULL key) at /Library/Caches/com.apple.xbs/Sources/CoreMedia/CoreMedia-1731.15.202/Prototype s/LegibleOutput/FigAgglomerator.c line 92

3/27/16 2:04:10.052 PM com.apple.WebKit.WebContent[888]: [14:04:10.052] <<<< IQ-CA >>>> piqca_setUsePreQueue: (0x7fee43bd9400) rejecting report of layer being serviced - IQ has not yet begun to update

3/27/16 2:04:12.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) ipc-posix-sem SandboxingDetectionTest

3/27/16 2:04:13.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) ipc-posix-sem SandboxingDetectionTest

3/27/16 2:04:14.415 PM com.apple.WebKit.Plugin.64[671]: GVA error: Flow_QT0::physicalAcceleratorDispose, m_physical_accel_created == false

3/27/16 2:04:14.418 PM com.apple.WebKit.Plugin.64[671]: [14:04:14.417] vtDecompressionDuctCreate signalled err=-12913 (err) (Could not select and open decoder instance) at /Library/Caches/com.apple.xbs/Sources/CoreMedia_frameworks/CoreMedia-1731.15.20 2/Sources/VideoToolbox/VTDecompressionSession.c line 1296

3/27/16 2:04:16.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) mach-lookup com.apple.dock.fullscreen

3/27/16 2:04:16.960 PM WindowServer[156]: _CGXRemoveWindowFromWindowMovementGroup: window 0x60 is not attached to window 0xd0

3/27/16 2:04:19.031 PM com.apple.WebKit.WebContent[888]: [14:04:19.031] <<<< Boss >>>> figPlaybackBossPrerollCompleted: unexpected preroll-complete notification

3/27/16 2:04:21.394 PM com.apple.WebKit.WebContent[888]: GVA error: Flow_QT0::physicalAcceleratorDispose, m_physical_accel_created == false

3/27/16 2:04:21.467 PM com.apple.WebKit.WebContent[888]: [14:04:21.467] FigAgglomeratorSetObjectForKey signalled err=-16020 (kFigStringConformerError_ParamErr) (NULL key) at /Library/Caches/com.apple.xbs/Sources/CoreMedia/CoreMedia-1731.15.202/Prototype s/LegibleOutput/FigAgglomerator.c line 92

3/27/16 2:04:24.720 PM WindowServer[156]: _CGXRemoveWindowFromWindowMovementGroup: window 0x60 is not attached to window 0xd0

3/27/16 2:04:25.646 PM WindowServer[156]: CoreAnimation: context hosting changed while locked!

3/27/16 2:04:28.000 PM kernel[0]: Sandbox: com.apple.WebKit(671) deny(1) mach-lookup com.apple.dock.fullscreen

3/27/16 2:05:02.000 PM bootlog[0]: BOOT_TIME 1459112702 0

Try a Safe Boot, holding SHIFT key at bootup, does that still do it?

What OSX version are you running?

To find out if it's system wide or user specific, try this...

Open System Preferences>Users & Groups, unlock the lock, click on the little plus icon, make a new admin account, log out & into the new account.

Does it work in the new account?

I'm using OS X 10.11.4. I have solved my problem for now by simply using Google Chrome and avoiding Safari until Apple solves the issue. I've not had a lockup since.

Thanks for the report. 🙂

Same issue with same device. I tried everything but not fixed.

Check this forum please:

http://forums.macrumors.com/threads/macbook-pro-2015-with-osx-el-capitan-10-11-4 -system-wide-safari-freeze.1963711/

Hi,

I can't tell what you posted there, you might start a new topic here to get more helpers in on it. 🙂