iCloud Photo Sharing / Safari sync on 5s, iOS 7.1.2

Hi Apple experts:

An iPhone 5s (A1457/A1530) running on iOS 7.1.2. During usage I observe battery life ( be it usage or standby ) about 1/3 lower than average.

Turned off iCloud service from the start of re-installing 7.1.2 (in DFU mode) last time already. Short battery life still observed since then.

Suspected that some processes are resource-hogging while phone is sleeping.

Connected to my Mac and using iPhone console in XCode to retrieve the following findings:

1: a.Symptom: mstreamd has been working even during sleep yet from the looks of it, it is stuck in an infinite loop.

Below's an excerpt of the device log:

Aug 14 11:39:06 Ts-iPhone mstreamd[859] <Notice>: (Note ) mstreamd: Not monitoring for external power.

Aug 14 11:39:06 Ts-iPhone mstreamd[859] <Notice>: (Note ) PS: Media stream daemon stopping.

Aug 14 11:39:06 Ts-iPhone mstreamd[859] <Notice>: (Note ) AS: <MSIOSAlbumSharingDaemon: 0x137e5d6e0>: Shared Streams daemon has shut down.

Aug 14 11:39:06 Ts-iPhone mstreamd[859] <Notice>: (Warn ) mstreamd: mstreamd shutting down.

Aug 14 11:39:06 Ts-iPhone mstreamd[862] <Notice>: (Note ) mstreamd: mstreamd starting up.

Aug 14 11:39:06 Ts-iPhone mstreamd[862] <Notice>: (Note ) PS: Media stream daemon starting...

Aug 14 11:39:46 Ts-iPhone mstreamd[862] <Notice>: (Note ) mstreamd: Not monitoring for external power.

Aug 14 11:39:46 Ts-iPhone mstreamd[862] <Notice>: (Note ) PS: Media stream daemon stopping.

Aug 14 11:39:46 Ts-iPhone mstreamd[862] <Notice>: (Note ) AS: <MSIOSAlbumSharingDaemon: 0x15556e450>: Shared Streams daemon has shut down.

Aug 14 11:39:46 Ts-iPhone mstreamd[862] <Notice>: (Warn ) mstreamd: mstreamd shutting down.

Aug 14 11:39:46 Ts-iPhone mstreamd[865] <Notice>: (Note ) mstreamd: mstreamd starting up.

Aug 14 11:39:46 Ts-iPhone mstreamd[865] <Notice>: (Note ) PS: Media stream daemon starting...

Notice the 40 seconds interval between the 2 attempts - the interval pattern is consistent and every time it happens the cpu usage will have a 10~20% spike (monitored using Instruments courtesy of XCode).

b.Actions: Followed the tips Ashin shared in http://forums.macrumors.com/showthread.php?t=1715396&page=3

Worked for a while but mstreamd will come back after restarting / sitting aside for few hours.

Deleted iCloud acc on iPhone and it does not go off, stays in background running every 40 seconds till today.

2: a.Symptom: syncdefaultsd working every 2 minutes checking with server. See below for device log:

Aug 14 11:39:22 Ts-iPhone syncdefaultsd[863] <Notice>: (Note ) SYDAccount: no account

Aug 14 11:39:22 Ts-iPhone syncdefaultsd[863] <Notice>: (Note ) SYDPIMAccount: no account (null)

Aug 14 11:39:22 Ts-iPhone syncdefaultsd[863] <Notice>: (Note ) SYDAlwaysOnAccount: no account (null)

b. Actions: Safari bookmark sync in iCloud turned off -> no change.

Deleted iCloud acc on iPhone -> no change.

3. a. Symptom: webbookmarksd running in background since bootup. Observed using ActMonitor by Aeonika.

b. Actions: NIL since no matter I restrict Safari or SIGINT KILL it in XCode Instrument, it comes back eventually.

TL;DR - iCloud related services are still running in background every now and then even after turned off.

Do I need to reset iCloud documents & data service, or reinstall iOS in DFU? Can I restore my backups?

Please kindly advise further actions or workarounds. Looking forward to your reply.

Thanks in advance!