panic in recent RELENG_5 tcp code path
glebius at FreeBSD.org
Fri May 20 06:15:46 PDT 2005
On Fri, May 20, 2005 at 03:10:32PM +0200, Jeremie Le Hen wrote:
J> > according to the fact that the panic occured in dereferncing mbuf pointer
J> > your kernel is compiled without INVARIANTS.
J> > Please compile it with INVARIANTS. This will probably help to trigger panic
J> > earlier, and it will be more clear.
J> a quick look at src/conf/NOTES reveals the following :
J> # The INVARIANTS option is used in a number of source files to enable
J> # extra sanity checking of internal structures. This support is not
J> # enabled by default because of the extra time it would take to check
J> # for these conditions, which can only occur as a result of
J> # programming errors.
J> I'm going to recompile my kernel with INVARIANTS but I wonder in
J> which order of magniture it will slow my kernel down. In other words,
J> what does INVARIANTS do concretely, shall I expect a performance drop
J> like WITNESS does ?
No. The performance loss is _much_ less significant than in WITNESS case.
You probably will not notice it.
Totus tuus, Glebius.
More information about the freebsd-stable