GEOM Gate.

[Poul-Henning Kamp]

In message <20030817211627.GC2653 at dan.emsphone.com>, Dan Nelson writes:

>I think this just demonstrates that you should not run benchmarks with
>all your debugging flags enabled :)  Most people will not be running
>production systems with WITNESS, and parts of the kernel that bog down
>under the heavy load of WITNESS may work just fine on a regular kernal
>config.

To quote from src/UPDATING:

] NOTE TO PEOPLE WHO THINK THAT 5.0-CURRENT IS SLOW:
]         FreeBSD 5.0-CURRENT has many debugging features turned on, in
]         both the kernel and userland.  These features attempt to detect
]         incorrect use of system primitives, and encourage loud failure
]         through extra sanity checking and fail stop semantics.  They
]         also substantially impact system performance.  If you want to
]         do performance measurement, benchmarking, and optimization,
]         you'll want to turn them off.  This includes various WITNESS-
]         related kernel options, INVARIANTS, malloc debugging flags
]         in userland, and various verbose features in the kernel.  Many
]         developers choose to disable these features on build machines
]         to maximize performance.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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Never attribute to malice what can adequately be explained by incompetence.