Speed up by removing modules

dyscoria · 2008-01-27 14:04:44

I'm currently in the process of deciding what modules to remove in order to speed up the boot process (significantly??? this might not even be worth it if boot times aren't affected that much).

However, there doesn't seem to be a good way to find out what each module does other than removing it and seeing what breaks. A few of them can be google seached, but for many others I don't know if it has broken something or not as I don't know what should be tested. Any advice on a better way to see which modules are unneeded would be appreciated.

FYI: So far i've removed ppp_generic and slhc as I don't use ISDN or dial-up. It seems eepro100 doesn't seem to be necessary for the ethernet connection to work. I've removed ieee1394 ohci1394 firewire_ohci firewire_core as my firewire slot isn't working anyway. Also removed battery as i'm using a desktop computer.

Last edited by Jamie (2008-01-27 14:18:39)

dyscoria · 2008-01-27 14:30:18

Also, how do I find out if i'm using SCSI? I have one hard drive that I think is SATA so i'm assuming I can get rid of the SCSI hook and the SCSI modules (sd_mod and sr_mod)

Thanks.

1311219 · 2008-01-27 14:57:55

You could try the modinfo command, as it gives a little hint in it's description output, and lsmod to see if a module you want to remove is required by some other module.
But generally, the best descriptions about different modules is available when configuring a linux kernel (like menuconfig) before it's compiled, which is a bit annoying...

As for improved bootspeed, I would say it doesn't make so much difference, with a few exceptions, like the ata_piix module, fore example, but when you start to remove those kind of things, you will remove allot of major hardware support (like losing ata/sata support). The most noticeable bootspeed (and normal performance) improvement would be when running a custom kernel, but most people don't like to have to compile a new kernel whenever newer versions comes out.

But still, good luck!

btw: Jamie, the simples way to find out is to look at the name of the (block) devices representing the drives (and the dmesg output), if, for example, it's just allot of hda1, hdb3 etc, and you don't even see a mention of scsi in dmesg, then you could try removing scsi support (but remember to have a fallback, just in case ), but if you have devices named things like sda1, sdb3 etc, or the dmesg output tells you some drive uses scsi, then don't remove it.

byte · 2008-01-27 16:22:54

SCSI is absolutely vital to any Linux system. You can't remove it.

schivmeister · 2008-01-27 18:48:37

and after this please provide statistics on the speed increase. Auto-loading all my modules on my compaq v3000 takes approx. 3 seconds.

goethe · 2008-01-28 14:45:47

You have already configured to load some of your daemons in background? That improved the boot time significantly for me

peets · 2008-01-28 22:25:02

While my computer boots I usually do some cleanup around the room or go grab a fruit to eat. Sometimes I'm even happy when my hard drives get their routine checkup - more time to improvise!

phrakture · 2008-01-29 00:53:44

This won't do much extra on boot (removing modules). In fact, it might actually make it longer if you're blacklisting them in rc.conf. Suffice to say I am working on making udev module loading faster.

dyscoria · 2008-01-29 17:14:09

phrakture wrote:

This won't do much extra on boot (removing modules). In fact, it might actually make it longer if you're blacklisting them in rc.conf.

Hmm that's exactly what i'm doing actually.

schivmeister wrote:

and after this please provide statistics on the speed increase. Auto-loading all my modules on my compaq v3000 takes approx. 3 seconds.

No noticable changes either good or bad so far so I think i'm just going to leave it as it is. Boot is not all that slow...i'm just a speed junkie Thought about compiling my own kernel, but don't think i'm quite ready for that business yet.

Last edited by Jamie (2008-01-29 17:14:38)

schivmeister · 2008-01-29 18:50:54

doing all those will not get you even a -10 second bootspeed boost But -5 is possible. Unless we're talking about static devs and no initram.

Last edited by schivmeister (2008-01-29 18:51:40)

dyscoria · 2008-01-29 20:03:47

schivmeister wrote:

Unless we're talking about static devs and no initram.

In a year's time maybe. At the moment though, this sort of thing breaks my mind

1311219 · 2008-01-31 16:29:34

Is there some special moment that takes extra long time? like uevents or the initcpio itself?

(my boot time (not including POST) is just above 20sec, including X11 and no module blacklist)

Arch Linux

#1 2008-01-27 14:04:44

Speed up by removing modules

#2 2008-01-27 14:30:18

Re: Speed up by removing modules

#3 2008-01-27 14:57:55

Re: Speed up by removing modules

#4 2008-01-27 16:22:54

Re: Speed up by removing modules

#5 2008-01-27 18:48:37

Re: Speed up by removing modules

#6 2008-01-28 14:45:47

Re: Speed up by removing modules

#7 2008-01-28 22:25:02

Re: Speed up by removing modules

#8 2008-01-29 00:53:44

Re: Speed up by removing modules

#9 2008-01-29 17:14:09

Re: Speed up by removing modules

#10 2008-01-29 18:50:54

Re: Speed up by removing modules

#11 2008-01-29 20:03:47

Re: Speed up by removing modules

#12 2008-01-31 16:29:34

Re: Speed up by removing modules

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