questions regarding compiling kernel

[omicron]

I have recently tried to recompile my rh7 kernel just so i can learn more about linux. I have followed the steps in the NHF. Most of the changes i made in the menuconfig wasn't obvious enought to tell from just using the computer normally so when i was booted in the new kernel, i again type make oldconfig and make menuconfig, but i see that all the config are back to the old kernel! does this mean that this new kernel has actually the same setting as the old one and i have miserably fail or this this config file the same regardless of how u compiled your kenerl. thanks in advance :confused: :confused:

PS. a small question, the purpose of compiling the kernel is to make it smaller and effecient right? but it confuses me, because if i were able to boot both kernel at my choice, wouldn't it mean the files and modules and the stuff are there in my hd anyway? i wouldnt' save any space nor other resources?

[slapNUT]

Did you happen to do a make mrproper before you did the make oldconfig? That would erase the .config file and you would get the default config file.



PS. a small question, the purpose of compiling the kernel is to make it smaller and effecient right? but it confuses me, because if i were able to boot both kernel at my choice, wouldn't it mean the files and modules and the stuff are there in my hd anyway? i wouldnt' save any space nor other resources?
The most important reason for kernel compiling is to make a customized kernel made specifically for your system. With the amount of ram and hard drive space on computers today the efficiency factor is not so important. What I mean is the amount of hard drive space a kernel and it's modules take up are minuscule by todays hard drive standards. Also the amount of ram a kernel consumes is also a small percentage of the total available. But when you get into computing cycles... thats where having a customized kernel can improve your performance.
There is only one kernel32.exe with every release of Windows and everybody on earth gets the same one and is stuck with it till they get enough money to buy the next version. I've have probably 10 kernels on this one computer and I only bought it last Christmas.

[omicron]

thanks for you input, i did make mrproper, so i pesume that's why i still have that same config and perhaps i didn't fail in compiling the kernel after all. :)

but according to you, with a updated PC, there would be no reason to compile kernel? since it would make small difference anyway? thanks