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This message is always displayed in the console log at regular intervals.

com.apple.xpc.launched: (comm.apple.imFoundation.IMRemoteURLConnectionAgent) the _DirtyJetsamMemoryLimit key is not available in this platform

Can anyone explain why it's displayed and if it has any impact on system performance, as well as how to get rid of it?

grg
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erwin
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    I have the same message on two Yosemite machines (one an upgrade from Mavericks, the other a clean install). Hours of Internet searching has left me empty-handed… all the results referred to iOS programming (so maybe it's an issue with a shared codebase?). Perhaps it just requires a 10.10.1 update from Apple. – Dustin Wheeler Nov 14 '14 at 19:51
  • Same issue here. Console log below. No real errors that I see, but it did take almost a full minute to load. 4/17/15 10:31:11.583 AM com.apple.xpc.launchd[1]: (com.apple.imfoundation.IMRemoteURLConnectionAgent) The _DirtyJetsamMemoryLimit key is not available on this platform. 4/17/15 10:31:52.000 AM kernel[0]: AppleCamIn::power_on_hardware 4/17/15 10:31:53.292 AM AppleCameraAssistant[373]: StartHardwareStream: creating frame receiver: 1280 x 720 (420v) [12.00,29.97]fps –  Apr 17 '15 at 14:32
  • Same issue here. I'm on macOS 10.13.4 High Sierra. – neoneye May 27 '18 at 20:33

1 Answers1

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It's harmless. Jetsam is a system that monitors memory use in OSX and iOS. It keeps a list of processes on the device, to monitor for situations where a device is running out of free RAM and look for things to kill to free up RAM. It also watches for processes that are using too much RAM; breaching a "high water mark" level.

This error message is because the code is shared between OSX and iOS but the _DirtyJetsamMemoryLimit key is only available on iOS.

You can read more about Jetsam at the following link.

http://newosxbook.com/articles/MemoryPressure.html

And if you are really interested you can read some of the Jetsam code in the following two files.

http://www.opensource.apple.com/source/xnu/xnu-1456.1.26/bsd/kern/kern_memorystatus.c http://www.opensource.apple.com/source/xnu/xnu-1456.1.26/bsd/sys/kern_memorystatus.h

Long story short, I don't think this error message necessarily indicates a performance problem. The memory system on iOS is a lot more strict because iOS doesn't have things like swapfiles that allow the system to exceed the physical amount of RAM. OSX has a lot more room to play in.

Anyone can verify that it has no impact on performance by using Activity Monitor and showing all processes in the CPU view. Look at the syslogd line and make sure the CPU time is reasonable compared to other tasks you wish to perform with your Mac.

Alistair McMillan
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    Ok. So there is no connection between this _DirtyJetsamMemoryLimit and repetitive crashes on Yosemite? –  Feb 11 '15 at 14:46
  • @Domnuldid No connection. I have stable Macs logging this error message all the time, so there's no clear indication that they are anything but coincidental. – bmike Feb 11 '15 at 15:04
  • @bmike Are we sure that sysmond has anything to do with Jetsam? I was under the impression that Jetsam is entirely contained within the kernel, and sysmond is just to feed things like Activity Monitor and top. – Alistair McMillan Feb 14 '15 at 00:52
  • @AlistairMcMillan Forgive my error - syslogd is the related daemon that would show excessive IO/CPU due to log file processing and log message routing. You are correct about sysmond – bmike Feb 14 '15 at 02:58
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    if the code is shared between iOS and OS X then Apple des should filter the output log messages ... not displaying messages related to iOS on OS X computer... the system log is becomeg as long as the Bible... – erwin Mar 19 '15 at 11:39
  • @AlistairMcMillan, This fker crashed me while I'm working halfway. How can I disable Jetsam? – Pacerier Aug 28 '17 at 06:13
  • Correction: iOS does have swapfiles, at least since 12.4 (I jumped directly from 10.2.1 to 12.4, so I can’t say exactly when it started). They reside in /var/vm/swapfile0 on my iPad Pro 9.7” in 128MB units and I’ve seen it fluctuate between none, and 2 swapfiles (256MB). These are correctly reported as encrypted swap memory in Jonathan (NewOSXBook)’s console iOS tools: htop and procexp. – Syclone0044 Jan 19 '20 at 07:59