Linux v2.6 Begins Testing

← Back to Stories (view on slashdot.org)

Posted by CmdrTaco on Monday July 14, 2003 @01:01AM from the brace-for-destruction dept.

xose quotes Linus from the kernel list: "the naming should be familiar - it's the same deal as with 2.4.0. One difference is that while 2.4.0 took about 7 months from the pre1 to the final release, I hope (and believe) that we have fewer issues facing us in the current 2.6.0. But very obviously there are going to be a few test-releases before the real thing. The point of the test versions is to make more people realize that they need testing and get some straggling developers realizing that it's too late to worry about the next big feature. I'm hoping that Linux vendors will start offering the test kernels as installation alternatives, and do things like make upgrade internal machines, so that when the real 2.6.0 does happen, we're all set." You all know what to do ;) Update: 07/14 17:49 GMT by S : OverNeith writes "Joe Pranevich has done it again! He's written another summary document on what to expect in the new and upcoming 2.6 Kernel!"

22 of 361 comments (clear)

Min score:

Reason:

Sort:

Re:Difference? by pe1rxq · 2003-07-14 01:12 · Score: 5, Informative

The biggest change for normal users is the preempt patch, it will make your system very responsive to interactive tasks (ie a graphical desktop) also the new schedulers should help here.

Jeroen

--
Secure messaging: http://quickmsg.vreeken.net/
Re:I don't know what to do - really by pe1rxq · 2003-07-14 01:15 · Score: 4, Informative

You connect another computer to the serial port and use it as a console...
Or use multiple monitors, one for X, one for the console...
(with the serial solution you can automagicly log it and don't have to type anything from a screen)

Jeroen

--
Secure messaging: http://quickmsg.vreeken.net/
Re:I got it before the /.ing by caluml · 2003-07-14 01:17 · Score: 4, Informative

That's devfs. If you don't use that, they'll all be normal (hda, sdb, fd0, etc).
At least it wasn't mandatory as of 2.5.69 anyway.
Why isn't devfs the default now - it's been working fine for ages - for me anyway.

--
Get your own free personal location tracker
Re:This is a big deal. by avalys · 2003-07-14 01:18 · Score: 5, Informative

You don't have to wait - pretty much all of big stuff has already happened in the 2.5 series. 2.6 is the next stable series, which (usually) means no big architectural changes. What's going on now is testing to ensure that the 2.5 series is stable enough to be considered for a release as "2.6.0".

--
This space intentionally left blank.
Re:I got it before the /.ing by bumby · 2003-07-14 01:19 · Score: 5, Informative

For example. /dev/hda, /dev/hdb/, /dev/hdc now become /dev/discs/disc0, /dev/discs/disc1, /dev/discs/disc2

That is called devfs, and as far as I know is an optional thing. At least it was in 2.4-series, and I really really doubt it isn't in 2.5 and will be in 2.6. So just skipp the CONFIG_DEVFS_FS and CONFIG_DEVFS_MOUNT and use your old nodes.

--
Hey! That's my sig you're smoking there!
Re:Difference? by Libor+Vanek · 2003-07-14 01:19 · Score: 5, Informative

And better USB support with easier way for writing drivers for various USB gadgets.
Re:This is a big deal. by sfraggle · 2003-07-14 01:22 · Score: 5, Informative

I personally can't wait to skim the change logs.
Kernelnewbies.org has a page which usefully summarises the new stuff in 2.6.

--
were you expecting to see a sig here? perhaps you'd rather see the inside of an ambulance!
How's the must-fix list going? by Bollie · 2003-07-14 01:23 · Score: 4, Informative

Last time I looked at ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/ must-fix/ there were still some showstoppers. It seems like they were updated about a month ago, so I guess progress must have been made on them...

The biggest problem I have with the newer kernels is probably some ACPI/IRQ routing bug in my board. It's a common problem with the NForce2 chipset (APIC doesn't work, so you have to boot with pci=noacpi or acpi=off). It's not the biggest inconvenience, but it causes half of my unused USB slots not to work...

I must say the snappiness of 2.6 is great! I'm looking forward to beta-testing. AFTER I backed up my drive, of course!
Re:Difference? by Wiz · 2003-07-14 01:25 · Score: 4, Informative

The best reference I've found is Dave Jones' website..... Linux 2.5 core updates.
Re:devfs? by rjw57 · 2003-07-14 01:26 · Score: 4, Informative

Actually devfsd does (see here). Most distros use DevFS + devfsd these days (notable exeption off the top of my head is RedHat).

--
Rich
Re:Sorry by Surak · 2003-07-14 01:34 · Score: 5, Informative

Actually, it *is*. It's in the portage tree under sys-kernel/development-sources development-sources-2.6.0_beta1.ebuild

--
My journal has hot /. gossip.
Re:Difference? by inode_buddha · 2003-07-14 01:38 · Score: 5, Informative

Yes, IPSEC is already in 2.5.xx, along with the NSA's SELINUX hooks, IBM's JFS filesystem, and SGI's XFS filesystem. Lots of VM and block I/O work, too.

--
C|N>K
Re:timeslice and 'hyperthreading'?? by nilsjuergens · 2003-07-14 01:43 · Score: 5, Informative

Replying to point (2):

The scheduler in 2.6.xx is hyperthreading-aware.
It knows that switching a process from one hyperthread to another on the same cpu is less expensive than switching to another physical cpu (becaus both first- and second-level cache reside on-die), but it also tries to balance load on physical cpus.

While >=2.4.19 supported hypterthreading up to a certain point it happend that two processes were running on the same cpu while the other (physical) cpu was running idle. This does not happen with the new ht-aware scheduler.

Look here for a (compressed) version of the initial discussion.

--
-- Having problems sending big files over the net? Try out Efisto (http://efisto.org)
Re:timeslice and 'hyperthreading'?? by groomed · 2003-07-14 01:47 · Score: 4, Informative

The HZ value which determines scheduler granularity has been bumped from 100 (which gives 10ms granularity) to 1024 since 2.5.low-twenties or something. You can change the HZ value yourself on 2.4 kernels right now in fact.
Haven't heard much about scheduler/hyperthreading interaction.
Re:How to install? by caluml · 2003-07-14 01:59 · Score: 4, Informative

Very rough old notes.
Should help though
http://gk.umtstrial.co.uk/~calum/2.5-kernel/
Might update it if I get a few hits.

--
Get your own free personal location tracker
Re:Works, but no nvidia by defMan · 2003-07-14 02:11 · Score: 4, Informative

Take a look at minion.de. They have patches for getting NVIDIA's driver going.
word of warning by Maimun · 2003-07-14 02:22 · Score: 5, Informative

According to Alan Cox, there are security issues with 2.5.* (and thus with 2.6-test1)
Last time I checked there were remote DoS attacks and local root attacks present in 2.5.7x
See:
Re: Linux v2.6.0-test1
The whole thread is here Linux v2.6.0-test1
Re:Difference? by Miles · 2003-07-14 02:32 · Score: 4, Informative

They're using the new NTFS drivers. Check out:
http://linux-ntfs.sourceforge.net/
Re:BIO by kill-1 · 2003-07-14 02:36 · Score: 5, Informative

From Dave Jones' write-up (link in the post above)
CD Recording. ~~~~~~~~~~~~~ - Jens Axboe added the ability to use DMA for writing CDs on ATAPI devices. Writing CDs should be much faster than it was in 2.4, and also less prone to buffer underruns and the like. - Updated cdrecord in rpm and tar.gz can be found at *.kernel.org/pub/linux/kernel/people/axboe/tools/ - With the above tools, you also no longer need ide-scsi in order to use an IDE CD writer. - Ripping audio tracks off of CDs now also uses DMA and should be notably faster. You can also find an updated cdda2wav at the same location. - Send good/bad reports of audio extraction with cdda2wav and burning with the modified cdrecord to Jens Axboe - Currently only 'open by device name' works in cdrecord. cdrecord -dev=/dev/hdX -inq - More info at http://lwn.net/Articles/13538/ & http://lwn.net/Articles/13160/
Re:timeslice and 'hyperthreading'?? by TeknoHog · 2003-07-14 02:37 · Score: 4, Informative

You can change the HZ value yourself on 2.4 kernels right now in fact.
I think it requires the CK patch to change it. The patch also includes other low latency features which can be quite useful.

--
Escher was the first MC and Giger invented the HR department.
Re:Have they fixed SBP2 yet? by Cthefuture · 2003-07-14 02:44 · Score: 4, Informative

Well, assuming that's a legitimate question and you're not just being a smart-ass (hard to tell)...

I used rfstool.

--
The ratio of people to cake is too big
Still the same problems since 2.5.68 by hacker · 2003-07-14 02:49 · Score: 5, Informative

2.6.0-test1 is MUCH slower than 2.4.21 or 2.4.21-preempt-rml here. I see that the timing issues are still not fixed in 2.6.0-test1, and haven't been working since 2.5.68. I've reported this at least a dozen times to the appropriate people, with no fixes eminent yet.
To test this issue out, run Sawfish, and bind a key like Ctrl-Alt-B to a black-background xterm. Launch X, and run Sawfish. Hit Ctrl-Alt-B once and see what happens. It's consistant here across about 6 machines, all different hardware.. a 3-4 second delay, then anywhere from none to 4 xterms will open up. On 2.4.anything, it opens the xterm instantly, and only opens one of them, not 3, not none.
The other issue is that there's some underlying change in the TCP stack/net drivers that cause rsync and anything running over ssh/ipsec to fail with weird dropped-socket errors from the applications using them. Again, on 2.4, it works flawlessly.
It's very annoying, and both of these are blockers for me and most of the machines I'd be running this on. It happens with anything that involves keyboard shortcuts; menu accels, launched applications, keybindings, everything.
Changing to the different schedulers does not help; deadline, as, or cfq. 2.5.68 worked perfectly, and didn't have these anomalies, but every single kernel since that time, has had it. I've diffed, and I can't tell which of the dozens of changes actually broke this.
If anyone has a solution, I'm all ears.