Arch Linux

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

DracoLinux and very slow hard disk I/O

Just last night I gave DracoLinux a try on my laptop - it's basically Sl;ackware with pkgsrc.  It's generally pretty nice, though the package managment isn't quite as advanced as pacman... Unfortunately I've got a problem with speed, though. Hard drive I/O is amazingly slow on Draco, easily ten times slower than on Arch - writes, at least, seem to take a lot longer, and read performance also seems to be affected. I checked the hard drive settings with hdparm, and lo and behold everything looked normal, with udma5 enabled; and I'm pretty sure the loopback interface is up. Yet, installing the kernel takes five minutes, and formatting my partitions takes twenty - the install CD also gives me slow I/O.

What am I missing here? I know this can't be normal behavior...

(If it helps, my laptop's mobo uses a chipset supported by the piix module, and my hard drive is PATA, not SATA...)

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: DracoLinux and very slow hard disk I/O

Okay I found the problem, it looks like Intel combined mode is being used even though it isn't needed. Bah.

How do I turn off the use of IDE drivers wholesale? I can disable IDE for individual drives with hdx=noprobe, but that's ugly, and combine_mode=libata doesn't work...

patroclo7

Member

From: Bassano del Grappa, ITALY

Registered: 2006-01-11

Posts: 915

Re: DracoLinux and very slow hard disk I/O

I have used draco 0.3 for a couple of months and I remember the same slowness of pkgsrc you described in the draco forums: probably I was victim of the same issue.

I really do not know how to help you, I think that PATA and IDE simply should not be compiled both into the kernel: if you recompile the kernel with IDE out or as modules, you should solve your problems. However, I remember vaguely LOTS of problems when trying to compile a newer kernel release in draco. While the kernel worked fine and solved that slowness issue, there was a mismatch between the actual kernel version and lots of references to the expected kernel version in pkgsrc-related configuration files, anmd pkgsrc complained with bunches of errors. The developer replied to me that actually I was not expected to upgrade manually to a new kernel, because this was against the dracolinux-BSD philosophy of having a stable, fixed basis separated from all the rest, which is managed by pkgsrc. Due to this kind of problems and to the awkward file system hierarchy (with all the stuff managed by the package manager in /usr/local and no place for autonomously compiled software and scripts: and they are needed, because many apps are not in pkgsrc, and it is not an easy task at all to create a pkgsrc recipe), I finally abandoned Dracolinux.

Last edited by patroclo7 (2008-07-25 12:25:49)

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Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: DracoLinux and very slow hard disk I/O

Hey it's olear... Cool.

olear: thanks for the advice. I'd kind of prefer not to use a custom kernel, but if I wind up using Draco again and see this problem, I'll see if it works.

The best solution seems to me to be preloading the PATA modules I need on boot, though. I do recall there being a way of doing that from the bootloader, but it escapes me at the moment. Alternatively I could try messing around further with combined-mode stuff - could be I missed something there.

(On most machines the BIOS apparently lets you turn off combined mode for Intel chipsets, but my laptop's BIOS sucks.)

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: DracoLinux and very slow hard disk I/O

Bleh. Even with hdx=noprobe, hard drive performance is vastly inferior to what I see on Arch.

Olear: due to the commonality of Intel chipsets, I would recommend sticking with either IDE or PATA drivers for the kernel - preferably PATA, though perhaps IDE would be better with the older kernel used by Draco. It's your choice though.

patroclo7

Member

From: Bassano del Grappa, ITALY

Registered: 2006-01-11

Posts: 915

Re: DracoLinux and very slow hard disk I/O

While the kernel worked fine and solved that slowness issue, there was a mismatch between the actual kernel version and lots of references to the expected kernel version in pkgsrc-related configuration files, anmd pkgsrc complained with bunches of errors.

When you build packages in pkgsrc the package will contain reference to the kernel used when building, pkg_add will complain if you run another kernel, but it should work as usual.

A bit of time is elapsed, so my memory could fail. I remember vaguely that the problem was with the URL where dracopkg looked for draco packages before passing to pkgsrc for the compilation: it seemed to look for a path including some output of uname (such as 2.6.24), whereas the packages were at a URL including 2.6.23. And I was not able to find the configuration file where this can be modfied, but I am sure that it can be modified, so probably it was just me and my laziness. Moreover I was innacurate in talking about a problem with pkgsrc while it probably concerned dracopkg, sorry. 

The developer replied to me that actually I was not expected to upgrade manually to a new kernel, because this was against the dracolinux-BSD philosophy of having a stable, fixed basis separated from all the rest, which is managed by pkgsrc.

I have never said this

Really sorry for this, probably I was confusing your words with those of someone else.

/usr - System
/usr/local - pkgsrc
/opt - Local

Yes, this is a solution. Still I think that it is not very logical: what is managed by pkgsrc is "third-party", but it is not"local" in any way (it is not even necessarily locally compiled since you can install binaries).  That is why BSDs use /usr/pkg, I guess.

pkgsrc can be a bit complicated at first, but it's a very good package manager.

I hope to come back to draco soon and learn more about pkgsrc. At first I was intimidated in particular by the extreme abundance of its output and by the difficulties in creating a package. But I know that there are lots of documentation about it which I should read.

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Mortuus in anima, curam gero cutis