I have not even decided if I want to undertake a kernel build, but for the sake of discussion, if everything happens to be in the stock kernel, why, other than file bloat, would you want to build a custom kernel? In FreeBSD, you can remove all those devices and drivers that are not needed, and, depending on how much stuff you add or delete, can make a decent size reduction in the kernel itself. I'm not smart enough to know if there is a performance trade-off with a whole bunch of unneeded modules or drivers in the kernel, but perhaps common sense tells me that there must be some kind of performance hit otherwise. Kernel building in Linux is very much different from the BSD camps, and I'll admit I'm not sure I understand enough about the Linux build process to undertake it. Comments appreciated...... -- Snowman
On Thu, 2005-09-22 at 09:52, Sam Drinkard wrote:> I have not even decided if I want to undertake a kernel build, but for > the sake of discussion, if everything happens to be in the stock kernel, > why, other than file bloat, would you want to build a custom kernel? In > FreeBSD, you can remove all those devices and drivers that are not > needed, and, depending on how much stuff you add or delete, can make a > decent size reduction in the kernel itself. I'm not smart enough to > know if there is a performance trade-off with a whole bunch of unneeded > modules or drivers in the kernel, but perhaps common sense tells me that > there must be some kind of performance hit otherwise.Nearly all drivers are built as modules which have no effect on the kernel if you don't load them. If the disk space used by the module bothers you, you can remove the unused ones. The main downside to building them all is the time it takes to compile a kernel which most people don't need to do. -- Les Mikesell lesmikesell at gmail.com
I've needed int0 (timer) to be sharable, and to change the basic timing interval, so I've had to modify & compile kernels from 7.1->7.3 Since the hardware had 64MB RAM as a fixed limit, stripping the kernel of unnecessary stuff was also helpful. I''ve not yet dug that far with my new CentOS. Brian Brunner brian.t.brunner at gai-tronics.com (610)796-5838>>> lesmikesell at gmail.com 09/22/05 02:16PM >>>On Thu, 2005-09-22 at 10:57, Sam Drinkard wrote:> Les, is there any performance hit by using the stock kernel? One reason > I ask, is the application that hopefully will be running if we can get > the compile done is very number-crunching intensive. In fact, that is > about all it does do aside from generating a few files. Altho I've got > more than adequate horsepower to handle the job, I was just curious if > there were any "standard reasons" to either build or not build.I haven't built a custom kernel since the modular approach included everything I needed somewhere in the RedHat 6.x era. I can't think of any reason to do it other than needing to add drivers that won't work as modules. -- Les Mikesell lesmikesell at gmail.com _______________________________________________ CentOS mailing list CentOS at centos.org http://lists.centos.org/mailman/listinfo/centos ******************************************************************* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept for the presence of computer viruses. www.hubbell.com - Hubbell Incorporated