DTrace Hangout 01 September 2016

George will start on compressed output this week.

There are still 20 tests that fail so testing is not on by default.

Mark asks if the Apple folks always store argv or limit it the same way that FreeBSD does.

James mentions that even with a high switchrate you can lose data because the dtrace process might not be on CPU. This issue has been addressed for an upcoming release of Mac OS. They have the dtrace client sleep on a memory location and the kernel does a wakeup on that location when the buffer is 80% full.

People are starting to try the if() statement from Illumos but no one is really happy with this as it is. Since DIF has a ternary instruction we can do this on our own. There is a good test for how well this will work and whether or not having only forward branches will blow out the instruction limit. Samuel will update with the specific test.