# gentoo sources?

## rommel

i just rebuilt the kernel i had been running and i used the latest gentoo sources....my lsr lost like 15mb/s...its down to 68mb/s from the tranfer rates i was getting when i was running the vanilla kernel...whats the benefit of the gentoo kernel?...am i not configuring something right?

ciao

----------

## delta407

The Gentoo kernel is a heavily patched kernel prepatch (i.e. a pre-lease of 2.4.19); it is often a lot less stable, though in many cases faster.

----------

## rommel

well i just went back to the vanilla kernel and my hdparm reads went right back up....just think its strange...i am using lsr raid 0 on a resierfs / partition...then i was setting up another system with an lsi scsi host adapter using a sym53c1010 chip...and scsi cheetah drives....they were scoring less then ide drives....havent tried them with the vanilla kernel yet though...possibly it could be similar but i am not sure why they would be performing like ata drives when their seek time is like 3.6ms and they run at 15kLast edited by rommel on Mon Jun 17, 2002 7:12 am; edited 1 time in total

----------

## DArtagnan

 *delta407 wrote:*   

> The Gentoo kernel is a heavily patched kernel prepatch (i.e. a pre-lease of 2.4.19); it is often a lot less stable, though in many cases faster.

 

So you wanna say that vanilla is more stable and better than gentoo?

----------

## AutoBot

 *pacman wrote:*   

>  *delta407 wrote:*   The Gentoo kernel is a heavily patched kernel prepatch (i.e. a pre-lease of 2.4.19); it is often a lot less stable, though in many cases faster. 
> 
> So you wanna say that vanilla is more stable and better than gentoo?

 

Yes pacman vanilla is more stable, but I haven't had any issues with gentoo-sources other than the xfs/preempt and this is not gentoo specific.

----------

## delta407

Well, of course it's not Gentoo-specific, but they are still issues. I'm running a gentoo-sources kernel right now, actually -- nothing has blown up on me yet, and I'm willing to babysit this computer in case something does. But, in a production environment (or anything else where it has to work, or else) I would not run anything other than a vanilla kernel.

Kernel releases get tested, Gentoo kernels don't (except for a couple developers and the Gentoo users as guinea pigs). vanilla-sources is a lot more conservative than gentoo-sources (read README.gentoo and see what you're getting first).

Behold, the beauty of *nix: the choice is yours.

----------

## AutoBot

I wouldn't really refer to myself as a "guinea pig"  :Rolling Eyes: 

----------

## c_kuzmanic

Hmm, I think the term "Heavily patched Kernel" is a relative term, especially when applied to gentoo-sources. All the patches are listed in the gentoo-sources ebuild file, compared to red hat or mandrake kernels the patches are rather modest and few in number.

----------

## delta407

Diff it to 2.4.18 and you get... wait, let's see:

```
# ls -l linux-gentoo-2.4.19-gentoo-r7.patch.bz2

-rw-r--r--    1 root     root      6423812 Jun  6 22:00 linux-gentoo-2.4.19-gentoo-r7.patch.bz2
```

6.4 MB of patches bzip2'ed, which comes out to a 39 MB diff decompressed.

That's not heavily patched?

----------

## c_kuzmanic

From the gentoo-sources ebuild file:

#What's in this kernel?

#INCLUDED:

#	from http://www.kernel.org (ac):

#		2.4.19-pre7-ac2

#		removed the software suspend patch; it can be dangerous and

#		conflicts with the new ACPI

#	from http://oss.sgi.com/projects/xfs:

#		SGI XFS 1.1 (Official release code -- the most thoroughly tested)

#	from http://www.grsecurity.org:

#		grsecurity-1.9.4 (with 2 updates/fixes and a fix for an NVIDIA driver compile problem)

#	from http://www.zipworld.com.au/~akpm/linux/schedlat.html:

#  	2.4.19-pre7-low-latency

#	from http://luxik.cdi.cz/~devik/qos/htb/:

#	   	htb2 (QoS support)

#	from http://www.tech9.net/rml/linux:

#	  	preempt-kernel-rml-2.4.19-pre7-ac2-1.patch

#		preempt-stats-rml-2.4.19-pre5-ac3-1.patch

#	from http://www.infolinux.de/jp10:

#		40_TIOCGDEV.bz2

#		51_loop-jari-2.4.16.0.bz2

#		98_tkparse-4096.bz2

#	from http://www.kernel.org (aa):

#		00_3.5G-address-space-4

#	from http://www.sourceforge.net/projects/acpi:

#		acpi-20020503-2.4.18.diff.gz 

#		(This allows booting of Toshiba Satellite 5005-S507 "legacy free" laptops)

#		Added tweak so that CONFIG_PM is defined only if CONFIG_ACPI or CONFIG_APM is also

#		set.  Removed CONFIG_PM toggle from configuration.

#	from http://www.infolinux.de/jp13:

#		07_jiffies-for-i386 (tweaked so that 1000HZ is the default for x86)

#		54_mmx-init

#		55_p4-xeon

#		56_x86-fast-pte

#		58_acpi-lowerlatency-3

#		59_acpi-pciirq-18

#		60_acpi-y2k-1

#	from Blue Lizard <webmaster at dofty.zzn.com>:

#		A 2-line patch to enable compatibility with the new SiS 740/961 Athlon chipset

#	from http://www.sourceforge.net/projects/evms:

#		IBM Enterprise Volume Management System version 1.0.1

#	from linux-2.4.18-wolk3.4-rc5-patchset (http://www.sourceforge.net/projects/wolk):

#		102_amd_lvcool.diff

#		Allows slightly cooler running AMD Athlon CPUs in systems with VIA mobos

#	Additional fixes:

#		Marked ACPI option as "DANGEROUS" (because it is and can cause boot ooopses --

#		use it only if you need it)

#		Marked JFS filesystem option as "FOR TESTING ONLY" (current JFS code seems to

#		have super-bad peformance and easily triggerable locks)

#	from mjc's collection of patches:

#		vfat symlink patch.  Creating symlinks on vfat creates Windowsy .lnk files.

#		CDDA dma patch -- enables DMA for CD devices# 

No sorry, I don't not consider that a heavily patched kernel, and keep in mind that I am comparing it to a red hat or mandrake kernel. I'll say it again, compared to those kernels, gentoo-sources patches are few in number and moreover, their very economical and efficient. The only gentoo patch I ever had problems with was the low-latency patch and those problems would only manifest when I used low-latency and the pre-emptive kernel patches in conjunction. Also, the number of patches applied to a kernel says nothing about the quality/performance of that kernel, and from that perspective gentoo gets full marks.

----------

## delta407

I don't disagree. Redhat and Mandrake do apply more patches, but they are tested on a very wide range of hardware. gentoo-sources is not. I, for one, am currently running gentoo-sources. An earlier revision was giving me some trouble, so I went to vanilla-sources; but the current one seems stable enough.

Nonetheless, I maintain my stance that gentoo-sources has caused many problems that do not exist with vanilla-sources. Kernel prepatches are historically less stable than kernel releases, and gentoo-sources (as a prepatch) inherits this reputation.

----------

## c_kuzmanic

 *delta407 wrote:*   

> 
> 
> Nonetheless, I maintain my stance that gentoo-sources has caused many problems that do not exist with vanilla-sources. Kernel prepatches are historically less stable than kernel releases, and gentoo-sources (as a prepatch) inherits this reputation.

 

Yep, that's true, the forum is full of problem reports that can be traced down to kernel-patches not performing properly, especially hardware related issues.

----------

