Today when attempting to figure out why Google Hangouts would not start on my Mac after the application was re-enabled due to a permissions change, I noticed a large number of messages like the following:
6/10/15 10:20:14.000 AM kernel: Google Chrome He (map: 0xffffff804da160f0) triggered DYLD shared region unnest for map: 0xffffff804da160f0, region 0x7fff99a00000->0x7fff99c00000. While not abnormal for debuggers, this increases system memory footprint until the target exits.
After some research I found that this is a reported issue in the bug tracker for Chromium. At first I thought that maybe this was the cause of the problem I was having but that turned out to not be the case, simply removing the Hangouts app in Chrome and re-adding it fixed my issue. However, the sheer number of these errors makes the log a bit unwieldy. It turns out that there is a way to hide all these messages (thanks to the commenter in the Chromium bug thread!):
sudo sysctl -w vm.shared_region_unnest_logging=0
While it doesn’t help at all with Chrome’s memory issues or other UI issues on Mac OS X, it is rather nice to hide all those spurious messages from the system log.