Subject: Re: DaemonNews article about boot speedups
To: Hubert Feyrer <>
From: Jason R Thorpe <>
List: tech-kern
Date: 09/04/2000 19:59:05
On Tue, Sep 05, 2000 at 04:52:12AM +0200, Hubert Feyrer wrote:

 > I've just read the DaemonNews article about speeding up the NetBSD boot
 > process by saving SCSI device probes. I wonder if hardcoding devices in
 > the kernel would be of the same effect:
 > ahc0    at pci? dev 9 function ?        #HF# Adaptec AHA2940U, aic78x0 SCSI
 > scsibus0 at ahc0                        #HF#
 > sd0     at scsibus0 target 1 lun 0      #HF# SCSI disk: 2GB DORS (NT)
 > sd1     at scsibus0 target 2 lun 0      #HF# SCSI disk: 4GB DCAS (ccd0 part 1)
 > sd2     at scsibus0 target 4 lun 0      #HF# SCSI disk: 4GB DCAS (ccd0 part 2)
 > Without having any wildcard devices (scsibus*, sd?, ahc?) in the kernel. 
 > Will this have the same speedup effect, or are the devices in the kernel
 > config file still prone to expensive probes?
 > (I've written a perl script to generate such a optimized kernel config
 > file from a template and dmesg output long time ago, see

For direct-config busses, all devices are probed regardless of the contents
of the config file.  The config file is used to match devices to driver

        -- Jason R. Thorpe <>