On Tue, Sep 07, 2004 at 08:31:41PM -0400, Brian Fundakowski Feldman wrote: > On Tue, Sep 07, 2004 at 05:55:29PM -0600, Scott Long wrote: > > All, > > > > Since we are closing in on the 5.3 release, I've removed the kernel > > debugging options from GENERIC in RELENG_5. They can of course be > > re-enabled by adding the appropriate lines back in locally. However, > > from now on when filing a kernel-related bug report, make sure to > > enable WITNESS, INVARIANTS, and DDB/KDB to help determine the problem. > > It's not necessarily a good thing to disable INVARIANTS without verifying > it has a huge cost in performance. It would be invaluable finding more > bugs in production, and will likely be sorely missed. IT's also worth > noting DDB/KDB is broken anyway in fairly large ways (on i386, at least, > breakpoints don't work and even with the "fix" you get panics soon if > you really do try to use them). INVARIANTS does have quite a significant impact on performance. 5.3 + 4BSD + INVARIANTS 2205.39 real 3840.87 user 1583.64 sys 5.3 + 4BSD - INVARIANTS 1862.61 real 3752.97 user 1141.81 sys That's the 'make world' time for the same source tree built under different kernels. KrisReceived on Wed Sep 08 2004 - 16:32:46 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:38:11 UTC