The Caffeinated Penguin

musings of a crackpot hacker

VNC is too slow

| April 29, 2008

Okay, so the conventional (old) way to connect to other machines was through X (X is network aware). This had a problem with being insecure because it was unencrypted.

The new way to connect to other machines is through VNC. VNC is not secure either, but can be tunneled through SSH. The problem is, it is slow.

Now, X is fast – very fast. See, VNC uses a remote framebuffer and pumps raster data over the wire, but X sends data over the wire which is then rastered by the local graphics hardware – excellent for remote headless servers, etc. They don't even run an X server, just client apps.

Now, given modern ssh X11 forwarding, we can have the best of both worlds – an encrypted (and optionally compressed) ssh connection keeps it safe while the display is rendered on your shiny local hardware.

There are two ways to accomplish this:

(I) Full screen login on a separate vt.

This is easy:

(1) run gdmflexiserver from a login screen, or use the “switch user” feature. (2) select the “Secure Remote Login” session (3) login as your other login (needs a local account) (4) it will ask you what host you want to connect to – do so.

Issues:

  • It would be nice if this could be made a “one click”.
  • It doesn't exit cleanly – I have filed a bug about this.

(II) A nested X server

(1) Run the X server with a basic xterm

xinit /usr/bin/xterm -display :1 — /usr/bin/Xephyr -nolisten tcp -ac -screen 1280×1024 :1

(2) Then just ssh over to your remote machine and run whatever session you like (such as startxfce4)

Issues:

  • It would be nice to have xinit just exec the ssh itself, but that seems to not set the display correctly – I don't know why.
  • There is no nice way to switch in and out of full screen – you either do full screen or windowed, but cannot toggle between them.

I should also mention that you can get a windowed version of (I) by running gdmflexiserver --xnest

Ubuntu Followup

| April 28, 2008

After reloading my desktop machine (instead of an upgrade from the previous version, I did a fresh reload), I notice that thunderbird and firefox actually use less memory on that machine than on my laptop. This is likely due to some differences in builds (laptop is AMD64, desktop is i386), but can a simple architecture change account for such a large variety in memoy footprint? On my i386 machine, they use up about half as much space. I wonder if there are other optimization differences – perhaps the logic is that AMD64 machines will have more memory and thus the compiler is optimizing for speed, where in i386 it is optimizing for space? If so, this is not a bad idea, because it is the case with my machines, and on i386, it is actually using LESS space (by about half) than on the previous versions included in Gutsy.

One unfortunate thing is that FireFox 3 Beta 5 (which comes in Hardy) does not perform well via VNC, which is how I end up doing work – I have one login and then do a vnc session which I run fullscreen. This actually is more convenient than a full separate login (easier to switch back and forth), and will work well when I move my work instance to a full virtual machine. However, the performance of FF3B5 is pretty abysmal, so I've installed FF2 which works much better.

I will post my full install procedure as well as general notes when I have a chance.

Learn to tie knots

| April 27, 2008

Knots are good

(we're having to learn them for firefighter class)

Ubuntu progress

| April 21, 2008

As a follow-on to my previous post about operating systems, I should probably talk about Ubuntu 8.04 LTS (Hardy Heron).

It is really good.

I've been running the beta pf the Xubuntu variant for about two weeks, which has now gone into Release Candidate status.

Various impressions:

  • NetworkManager seems to have finally gotten into working reasonably well and not breaking all the time. Hell, it doesn't even seem to be breaking at all, so far.

  • FireFox and Thunderbird are still memory hogs. Just looking at what is running right now, we see:

    9294 matt      20   0  777m 294m  25m S    2 14.6  30:07.45 firefox            
    9286 matt      20   0  788m 225m  28m S    0 11.2  31:06.04 thunderbird-bin
    

    It's kind of absurd.

  • I'm using the x86-64 (aka AMD64) build, and I don't know what folks are complaining about – the various bits and bobs install into the browser just fine. Flash movies play, and everything seems to work well.

Anyway, I'm going to upgrade all my machines to it once I have a chance, and I will be staying with this release until the next LTS release. The intermediary ones have just gotten too flaky.

I love my wife.

| April 20, 2008

I just spent six and a half hours fighting a brush fire, and I come home and she has made my peanut butter chocolate chip cookies.

Now that I've eaten several, it is time for bed.

Different Operating Systems

| April 19, 2008

So, over the last few months, I've been poking different distros/OS's to see what they all know. Please note that these represent their state when I played with them, which may not be the state now. I have tried to include version numbers if I remember.

PCBSD 1.5

Did not handle my scroll wheel on my mouse initially, but then did after I applied updates.

DesktopBSD 1.6

Did not handle video/monitor correctly. Stuck me in 800×600. PCBSD got this, but why not DesktopBSD.

FreeBSD 7.0-RC1

Installed just fine, booted on that machine, and then throws a pile of DMA errors about the disk and finally gives up and dies.

Some overall thoughts on BSD-en

The ports system is nice, but I'm kind of ambivalent on this whole “automatic compile from source” deal. With precompiled binaries, you can actually regression test stuff and be a little more confident that your builds work. PCBSD does add a precompiled binary package system, where DesktopBSD just added a friendly easy to use frontend on the ports system. I kind of like the latter approach a little better.

However, I have a reasonable expectation that a modern distro can set up X correctly. If my hardware is supported by X, it should be set up to work automagically.

Nexenta Core Platform 1.0

This is an interesting concept – OpenSolaris wearing a Debian “hat”, specifically using apt to do package management. This, coupled with ZFS, adds some really nice features – namely Transactional ZFS Upgrades.

However, under the hood, it is still Solaris and, to be trite about it, /dev/sda1 is easier for me to remember than /dev/rdsk/c0t0d0s0…

Now, it is really unfortunate that Sun doesn't want to play nice with ZFS. I mean, it's nice of them to let Java come out and play, but I would like some ZFS too.

Ultimately, I think Ubuntu is where it is at right now, so I'm going to keep using that for right now..

The purple Taurus pictures

| April 17, 2008

We cut this in a couple of spots, then spread it (which gave us like 27″ of space), and then we used the ram, which gave us another 54″ or so of space.. We cut the back door off (yes, it cuts through that stout bolt), and cut the roof off. Modern cars have a more heavily reinforced passenger compartment, but the cutting tools will cut through those too. The carnage. Doors? What doors? From the front. (Photos courtesy of Ed “My helmet was so new I had to put the stickers on it” Bailey.)

Computer follow up

| April 17, 2008

So, I was talking with a guy at work, and he had a really good point.

“If the AMD Phenom 9850 is about the same performance as the Intel Core 2 Quad Q6600, and they are the same price, then maybe you should decide based on what board you want, not what CPU you want”.

This was a very good point, so I started looking at the different boards, and I think I've settled on a Gigabyte GA-X48-DQ6. It has the following advantages over the ASUS M2A32-MVP:

  • One more PCIe slot
  • One more Gbit Ethernet Port
  • 2 more SATA ports

(at least, those are the ones which matter to me).

Now, the downside is that you lose 2 PCIe x16 slots. So, I end up with 2 PCIe x16's and 3 PCIe x1's, as opposed to 4 PCIe x16's (which will only run at x8 when fully populated).

Given the fact that many non-video cards are PCIe x1, I think it better to use those and keep the PCIe x16's running full speed.

So, it looks like it will be an Intel CPU for me.

Another side benefit is that Intel has a whole line of CPU's which are faster than the Q6600, but will fit in that board. AMD, on the other hand, is using the socket AM2+ as a stopgap until the AM3 comes out. This means that, in a couple years, I can pick up an Intel CPU which is perhaps 50% faster than the Q6600, but that I'm pretty much stuck with whatever I buy today in the AMD board. I'm not sure I would do this, but the possibility exists.

Oh, and one thing I'm really liking is the stuff I was having to spend a premium for (well engineered boards with good capacitors, quiet fans, etc.) are now becoming “high end hobbyist” rather than “server”. So, there are a pile of quality boards using good stuff and packed with features. These boards are designed to support overclocking.. so if I run everything within approved spec, it should run rock-solid stable for a very long time.

Anyway, dinner time.

Computermachine stuff

| April 16, 2008

So, I was originally going to get an AMD Phenom, but I've been looking at the benchmarks and the fix for the TLB bug just kills things. So, looks like it will be a Core 2 Quad….

Looks like the new computer will be a birthday present to me. 🙂

Edit: It looks like the fixed B3 stepping CPU's will be out by the time I go to buy my parts, so I'm going to be using an AMD Phenom with an ASUS M2A32-MVP board. The only downside I can find with that board is that there is only one LAN card. For now, this is not an issue, but I might add a PCIe ethernet card at some point.

Edit2: I should probably mention that I am under no illusions that the AMD CPU's have performance on par with the Intel Core 2 Quad CPUs – they are all slightly slower. They are also about $100 cheaper when you take into account the difference in costs of CPU and motherboard. I am okay with this.

Edit3: I should clarify Edit2. After reviewing some benchmarks, it appears that the Phenom 9850 is about the same speed (faster with some, slower with others) as the Core 2 Quad Q6600 while being the same price. Hopefully those will be out by the time I go to buy boxen.. 🙂

Playing with toys

| April 16, 2008

The fire dept has some money to buy a new auto extrication tool (often called the jaws of life).. Anyway, a rep from Holmatro came by and showed their stuff.

I got to cut the back door off a Ford Taurus. 🙂

My brother firefighter Ed took pictures – I'll post them here when he emails them to me.