Re: Really small kernel
At Mon, 08 Nov 2004 17:26:44 +, ognjen Bezanov wrote: > > Thanks for all the answers, > > In essence i want to keep the kernel small so that it boots up as fast > as possible. > > Plus the hardware is a 75mhz laptop with very little ram, i want to save > as much ram as i can for other programs, hence the need for a small > kernel. > > As far as modules are concerned, i was under the impression that the > kernel + modules would be bigger (size wise) then having everything > together in one. > > Do using (or not using) modules make a difference to the total size when > loaded into ram? > Removing module support from the kernel would save a bit, but I don't know how much. If it gets read of the kernel symbol table, it could save you some memory as my kallsyms file take about 500K. You will have to test though to see if you actually save that much in memory. As for the modules themselves, it means that you don't have to load the modules that you are not using at the moment, which could save you some memory (such as floppy, cdrom, serial, etc.) This way you also save the memory some of the modules allocate, how much that is would depend on the module though. The shouldn't be any other difference in memory usage otherwise when comparing compiling things as modules, compared to compiling into the kernel. What insmod does is basically dynamically link the code. Modules are regular object files, and insmod looks for the unknown symbols, and then tries to resolve them using the kernel's exported symbols (same as statically linking a regular object file actually, only done at runtime). > On Mon, 2004-11-08 at 16:21, Martin Theiß wrote: > > Hi ognjen Bezanov, *, > > > > ognjen Bezanov wrote: > > > > > Hi all, > > > > > > I want to find a way to find out what things i need to enable for my > > > laptop to function. > > > > > > I want to compile a kernel which only has support for the hardware im > > > using and no module support > > > > > Why no modules? Modules only have a slight overhead, when loading. After > > this they perform like built-in modules. > > > > > Is there any command which will let me view all the hardware on my pc > > > and what respective setting i need on my .config file? > > > > > lshw is a good tool to find out, what is in your laptop. also you should > > consider using lspci. both together should give you a really good overview. > > the only problem is to "translate" these infos into a .config. i don't know > > of any tool which is capabale of doing this job. > > the best way to do, what you want is running the distclean target of the > > kernel and starting with the allnoconfig target. from this startingpoint you > > can enable the different settings via menuconfig or similar. > > > > > I want to make the kernel as small as possible > > > > > Remember, size only matters at boot time (maybe 3-5% faster startup) or when > > you really don't have much ram available. > > > > Kind regards > > Martin > > > -- > To UNSUBSCRIBE, email to [EMAIL PROTECTED] > with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED] > > > +++ > This Mail Was Scanned By Mail-seCure System > at the Tel-Aviv University CC. >
Re: Really small kernel
On Mon, Nov 08, 2004 at 05:26:44PM +, ognjen Bezanov wrote: > Thanks for all the answers, > > In essence i want to keep the kernel small so that it boots up as fast > as possible. [snip] > > Do using (or not using) modules make a difference to the total size when > loaded into ram? I leave Module support turned on, but once I have a pretty clear handle on things, I just compile everything I want as built-in. I think that compiling things you rarely use as modules would probably save some working set memory. On a G3 powerbook, I disabled USB support completely, Firewire completely, PCMCIA completely, and compiled SCSI as builtin, IDE as builtin, Alsa as builtin, Network as builtin, NFS as builtin, SMBFS as builtin, ISO9660/Compressed/etc as builtin, but things like NTFS and VFAT as modules. It's not hard. You just do it. The decision tree for "make menuconfig" isn't that broad or deep. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Really small kernel
ognjen Bezanov wrote: Thanks for all the answers, In essence i want to keep the kernel small so that it boots up as fast as possible. Plus the hardware is a 75mhz laptop with very little ram, i want to save as much ram as i can for other programs, hence the need for a small kernel. As far as modules are concerned, i was under the impression that the kernel + modules would be bigger (size wise) then having everything together in one. Do using (or not using) modules make a difference to the total size when loaded into ram? I think that if you completely remove the ability to use modules (ie, a monolithic kernel), you can save some space with the kernel build. One of the kernel config options is to enable/disable modules. If you disable it, you will no longer have the option to compile stuff as a module. It's either in or out. Jason On Mon, 2004-11-08 at 16:21, Martin Theiß wrote: Hi ognjen Bezanov, *, ognjen Bezanov wrote: Hi all, I want to find a way to find out what things i need to enable for my laptop to function. I want to compile a kernel which only has support for the hardware im using and no module support Why no modules? Modules only have a slight overhead, when loading. After this they perform like built-in modules. Is there any command which will let me view all the hardware on my pc and what respective setting i need on my .config file? lshw is a good tool to find out, what is in your laptop. also you should consider using lspci. both together should give you a really good overview. the only problem is to "translate" these infos into a .config. i don't know of any tool which is capabale of doing this job. the best way to do, what you want is running the distclean target of the kernel and starting with the allnoconfig target. from this startingpoint you can enable the different settings via menuconfig or similar. I want to make the kernel as small as possible Remember, size only matters at boot time (maybe 3-5% faster startup) or when you really don't have much ram available. Kind regards Martin -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Really small kernel
Thanks for all the answers, In essence i want to keep the kernel small so that it boots up as fast as possible. Plus the hardware is a 75mhz laptop with very little ram, i want to save as much ram as i can for other programs, hence the need for a small kernel. As far as modules are concerned, i was under the impression that the kernel + modules would be bigger (size wise) then having everything together in one. Do using (or not using) modules make a difference to the total size when loaded into ram? On Mon, 2004-11-08 at 16:21, Martin Theiß wrote: > Hi ognjen Bezanov, *, > > ognjen Bezanov wrote: > > > Hi all, > > > > I want to find a way to find out what things i need to enable for my > > laptop to function. > > > > I want to compile a kernel which only has support for the hardware im > > using and no module support > > > Why no modules? Modules only have a slight overhead, when loading. After > this they perform like built-in modules. > > > Is there any command which will let me view all the hardware on my pc > > and what respective setting i need on my .config file? > > > lshw is a good tool to find out, what is in your laptop. also you should > consider using lspci. both together should give you a really good overview. > the only problem is to "translate" these infos into a .config. i don't know > of any tool which is capabale of doing this job. > the best way to do, what you want is running the distclean target of the > kernel and starting with the allnoconfig target. from this startingpoint you > can enable the different settings via menuconfig or similar. > > > I want to make the kernel as small as possible > > > Remember, size only matters at boot time (maybe 3-5% faster startup) or when > you really don't have much ram available. > > Kind regards > Martin -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Really small kernel
Hi ognjen Bezanov, *, ognjen Bezanov wrote: > Hi all, > > I want to find a way to find out what things i need to enable for my > laptop to function. > > I want to compile a kernel which only has support for the hardware im > using and no module support > Why no modules? Modules only have a slight overhead, when loading. After this they perform like built-in modules. > Is there any command which will let me view all the hardware on my pc > and what respective setting i need on my .config file? > lshw is a good tool to find out, what is in your laptop. also you should consider using lspci. both together should give you a really good overview. the only problem is to "translate" these infos into a .config. i don't know of any tool which is capabale of doing this job. the best way to do, what you want is running the distclean target of the kernel and starting with the allnoconfig target. from this startingpoint you can enable the different settings via menuconfig or similar. > I want to make the kernel as small as possible > Remember, size only matters at boot time (maybe 3-5% faster startup) or when you really don't have much ram available. Kind regards Martin -- Martin Theiß <[EMAIL PROTECTED]> GPG-Fingerprint: EC80 53A2 F0A2 6E6C 74D2 CB6E 002A F6D3 E78B 7F45 The box said 'Requires Windows 95 or better', so I installed Linux - TKK 5 signature.asc Description: Digital signature
