MacOS – How to make nsurlsessiond actions less anonymous to the user

high sierramacosNetwork

With the introduction of OS X Yosemite every once in a while little snitch (network monitoring program) pops up a requestor asking for permission to allow nsurlsessiond a connection to some ip address.

I understand that nsurlsessiond provides an API to allow any program using it to retrieve data via http or other supported protocol. In fact it acts like a proxy.

Is it possible to see which programs are using nsurlsessiond and of course what they use it for? I'm thinking of something like an access log file. Because in this current situation I am not able to do monitoring on applications using nsurlsessiond.

Best Answer

The 'more details' button should at least tell you who it's trying to contact, from which you may be able to decide whether to allow.

Possibly the main connections floater would give you more data…

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You could always drop in a request to obdev or even see if there's anything in the forum

I agree it would be a useful addition, to know what app is calling an API like that.

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MacOS Terminal – Enhancing Font Clarity

You can lighten the antialiasing system-wide in System Preferences. Go to General and at the bottom is a checkbox labeled "Use LCD font smoothing when available". This is pretty cool in theory, but Apple's implementation is... not so great. LCD font smoothing (also called subpixel rendering) treats the R, G, and B channels of each pixel as separate pixels, so you get something that looks even smoother. However, on a Mac it just doesn't work very well and you end up with the super-thick font.

Here's an animation of the two different antialiasing styles.

Animation of the different sizes

So all you need to do is uncheck the LCD font smoothing box and restart Terminal. (If you log out and back in or reboot, it should make the font better for the full UI.)

To off subpixel rendering for a specific application, use

defaults write com.apple.Terminal AppleFontSmoothing -int 0

changing com.apple.Terminal to the bundle ID. Change the 0 to a 1 to turn it on again.

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MacOS – How to know what nsurlsessiond is downloading

That daemon (or system process) is invoked and handles network download requests from many apps and many other services on macOS. (And iOS and tvOS and watchOS)

I haven't found an easy way to get summary details or statistics from the session manager, but since it works on a queue to upload or download things, my guess is you have one or more job(s) timing out.

Here are some ways to pick apart the activity on your system:

sudo lsof | grep nsurl
ps -ef|grep nsurl
sudo fs_usage -w | grep nsurl

The first lists open files and sorts for matches of “nsurl”. The second lists all processes and sorts again. The third lists file system activity.

That will let you monitor things and see which of the several nsurl daemons is running when you measure 400 mb of transfer. You can also get a dump of the system activity with sysdiagnose nsurlsessiond

If you determine that it's really iCloud Documents, you'll likely need brctl log -w to watch that subsystem instead of monitoring the worker threads that do the lifting.

Best Answer

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MacOS Terminal – Enhancing Font Clarity

MacOS – How to know what nsurlsessiond is downloading

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