is it me, or is tar slow?

yekibud · 05-02-2005, 01:28 PM

PC CHips, M952 Rev. 1.3B (Socket 478 - P4)

wpyh · 05-02-2005, 01:40 PM

Just a random guess, but maybe you didn't use an 80-wire cable?

yekibud · 05-02-2005, 01:47 PM

Yep, 80 little wires in the cable.

Shade · 05-02-2005, 10:52 PM

And you ran make bzImage and copied the new image to /boot and added a reference to it in lilo.conf and ran 'lilo' and rebooted?

:-)

--Shade

wpyh · 05-02-2005, 10:59 PM

I've tried reproducing your problem, so far there's only one working way:

(as root)
chmod 666 /dev/hdc
(then, as user)
hdparm -d1 /dev/hdc

which gives me:

/dev/hdc:
setting using_dma to 1 (on)
HDIO_SET_DMA failed: Permission denied
using_dma = 0 (off)

yekibud · 05-03-2005, 01:43 AM

wpyh: wow, thanks for the effort, man.

shade: well, more like make menuconfig, make, make install, make modules, make modules_install - but I don't think that's the problem.

Actually, guys, I think it really has to do with my VIA VT8237 chipset and the 2.6.xx kernel. I've been reading some pretty disturbing stuff about VIA support for Linux, shady deals with microsoft in dark alleys, etc.

I'm trying to find a work around, but so far it looks like this is the problem. Seems like the VIA823cxxx Linux driver just aint workin with a 2.6.xx kernel. I can't believe that though... *Somebody* has got to know a way to fix this - right? I mean, come on, this is Linux we're talking about. Anything is possible, right?

Am I right?

wpyh · 05-03-2005, 02:19 AM

Um... I didn't note that you're using 2.6, are you using udev? I'm using static devs, so my system would be a bit different. And I don't know anything about udev, but my guess is that if you use udev and get the permission error, maybe the udev daemon is somehow locking the devices and hdparm can't modify it? (so the ioctl returns an error and sets errno, which it prints out). See, my experiment shows that even though I can read and write to the /dev/hdc file (I assigned it rw-rw-rw-), I still can't ioctl on it because I lack some other permissions for executing the ioctl.

Can you try to use static devs and/or downgrading to 2.4, and see if that fixes the problem?

mdarby · 05-03-2005, 05:57 AM

I'm using VT8366 with no problems on 2.6.11.7.

Have you tried running tar on a different disk / mount?
How are your drives mounted in /etc/fstab?
What are the permissions on /dev/hd*?

yekibud · 05-03-2005, 07:20 AM

wpyh:
I have hotplug enabled, so that means I'm using udev, right? Running 2.4.29 everything's peachy - that's why I think it's a VIA support issue. However...

mdarby:
Your VIA driver works with 2.6, which shoots my theory, unless there have been some changes from 2.6.10 to 2.6.11, or VIA changes in the differing chipsets. I guess I could try 2.6.11, but do you think a change like this might be included in a 0.0.01 revision?

Tried the untar-ing with dma enabled on 2.4, and everything was zippy-fast - how it should be. So I'm pretty sure this is the issue, not which drive I'm playing with. But here's my fstab, anyway:

Code:

/dev/hda2        /                ext2        defaults         0   0
/dev/hda3	 swap 		  swap	      defaults	       0   0
#/root/swapfile  swap             swap        defaults         0   0
/dev/cdrom       /mnt/cdrom       iso9660     noauto,owner,ro  0   0
/dev/fd0         /mnt/floppy      auto        noauto,owner     0   0
none             /dev/pts         devpts      gid=5,mode=620   0   0
none             /proc            proc        defaults         0   0
/dev/hda1	 /mnt/hda1	  vfat	      defaults	       0   0
/dev/sda1        /mnt/sda1        vfat	      defaults 	       0   0

My permissions are all rw.

I'm hoping downgrading my kernel to 2.4 is not the 'solution' to this problem.

One other thing to note: I'm using the stock slackware 10.1 2.4.29-ide kernel where dma is working, whereas it's the slackware current-testing 2.6.10 with my own menuconfig that's not working. I'm wondering if there is just some combination of kernel parameters I'm not configuring that could make this work - but the 2.4 and 2.6 config files are different and long and I'm not sure how to start comparing them...

mdarby · 05-03-2005, 08:53 AM

Have you tried downloading fresh kernel source from kernel.org and using that to build the new kernel?

I normally compile everything I need into the kernel.

slackb0t · 05-03-2005, 09:23 AM

Quote:

Originally posted by mdarby

If you have modern hardware (newer IDE) you can try this tweak:

Code:

hdparm -c1 -X70 -u1 -d1 /dev/hda

*Use at your own risk!* I've never had a problem with the above tweak, but YMMV!
With the tweak, I get about 60MB/s from my drive, as opposed to the original 17MB/s [/B]

How would you reverse this tweak if you wanted to try it?? Just in case it didn't work out..

thx

ps sorry for asking a question in your thread.. just hoping for a quick response..

mdarby · 05-03-2005, 09:29 AM

@slackb0t

It depends on what your drive is originally set at.
Check hdparm's man page to see its options;
You can find your drive's current settings by doing

Code:

hdparm /dev/<device>

mdarby · 05-03-2005, 09:34 AM

I'm using the VT82C693A chipset on a testing server at my office on 2.6.11.4. Works like a charm.

Checking .config, it seems that the line

Code:

CONFIG_BLK_DEV_VIA82CXXX=y

is responsible.

wpyh · 05-03-2005, 12:29 PM

No, hotplug doesn't neccessarily mean udev. And it shouldn't be a permissions problem. What I mean by "lack of permissions" is something deeper... it's not just filesystem permissions, it's something in the kernel (I don't know what, but it's something to do with the drivers and the ioctls).

Like mdarby said, you should download and compile a new kernel.

yekibud · 05-03-2005, 04:33 PM

Shoot. That did it, man. Got 2.6.11.8 from kernel.org, did my usualy make menuconfig, and presto - everything works.

Looks like I was off-base thinking it was a VIA support issue. But what were all those driver support complaints I was reading on the VIA forums, then? Wierd...

Anyway, this thread isn't over. I'm gonna compare the .config files for both kernels and see what went wrong...

Thanks you guys, for all your help. Community, man, community.