Mike Meredith

The ARM Servers Are Coming!

 Computing  No Responses »
Oct 312011
 

According to a couple of articles on The Register, a couple of manufacturers are getting close to releasing ARM-based servers. The interesting thing is that the latest announcement includes details of a 64-bit version of the ARM processor, which according to some people is a precondition for using the ARM in a server.

It is not really true of course, but a 64-bit ARM will make a small number of tasks possible. It is easy to forget that 32-bit servers (of which there are still quite a few older ones around) did a pretty reasonable job whilst they were in service – there is very little that a 64-bit server can do that a 32-bit server cannot. As a concrete example, a rather elderly SPARC-based server I have access to has 8Gbytes of memory available, is running a 64-bit version of Solaris (it’s hard to find a 32-bit version of Solaris for SPARC), but of the 170 processes it is running, none occupies more than 256Mbytes of memory; by coincidence the size of processes is also no more than 256Mb.

The more important development is the introduction of virtualisation support.

The thing is that people – especially those used to the x86 world – tend to over-emphasise the importance of 64-bits. It is important as some applications do require more than 4Gbytes of memory to support – in particular applications such as large Oracle (or other DBMS) installations. But the overwhelming majority of applications actually suffer a performance penalty if re-compiled to run as 64-bit applications.

The simple fact is that if an application is perfectly happy to run as a 32-bit application with a “limited” memory space and smaller integers, it can run faster because there is less data flying around. And indeed as pointed out in the comments section of the article above, it can also use ever so slightly more electricity.

What is overlooked amongst those whose thinking is dominated by the x86 world, is that the x86-64 architecture offers two benefits over the old x86 world – a 64-bit architecture and an improved architecture with many more CPU registered. This allows for 64-bit applications in the x86 world to perform better than their 32-bit counterparts even if the applications wouldn’t normally benefit from running on a 64-bit architecture.

If the people producing operating systems for the new ARM-based servers have any sense, they will quietly create a 64-bit operating system that can transparently run many applications in 32-bit mode. Not exactly a new thing as this is what Solaris has done on 64-bit SPARC based machines for a decade. This will allow those applications that don’t require 64-bit, to gain the performance benefit of running 32-bit, whilst allowing those applications that require 64-bit to run perfectly well.

There is no real downside in running a dual word sized operating system except a minor amount of added complexity for those developers working at the C-language level.

Greedy Pigs In The Boardroom

 General, Politics  No Responses »
Oct 292011
 

Yesterday we learned that UK company directors managed to screw the public, the shareholders, and the people working in the companies they direct by getting awarded pay rises amounting to 50%. Chief executives (who do a little bit more work) managed to grow their pay by 43%.

Of course the unions were up in arms, but this is bad enough that even the Tories are a little uncomfortable with the repugnant greed, and David Cameron has called for “transparency” in the boardroom. Whatever that means – after all we know that these guys are greedy pigs, what do they need to be more transparent about?

The likelihood of any company board paying the least bit of attention to a polite request to act with restraint is about the same as the chance of a snowball in hell lasting more than a minute. After all these people are quite happy to be known as greedy pigs … they have spent years and sometimes decades working themselves into a position where they can make themselves repeatedly sick eating from the trough of the economy.

The CBI on the other hand has trotted out the tired old excuse of having to pay salaries sufficient to attract the best in the world.

Which is true to a certain extent (although I doubt that every company director – many of whom do not work full time – deserves quite as much as they get), but is not quite the whole story.

Every year it seems that the top-level executives see at least double-digit income growth, whilst people who actually do real work see far less than that. Over time it leads to an increasing gap between the income of the richest and the rest of us. This is normally phrased as a gap between rich and poor, but that is just as wrong as ridiculously high salaries. It isn’t a gap between rich and poor, but a gap between the richest 1% and the rest of us.

Conventionally we accept these sort of things because superior company directors are supposed to ensure that companies become healthier and more profitable, causing the economy as a whole to become healthier with more resources to spread around. In other words the rich get richer, and so do the rest of us. But this doesn’t seem to be the case.

Sometimes we forget what an economy is for. It isn’t to make the rich richer, but to ensure that all the population get a share of the wealth so they have enough to eat, a place to live in, etc. If there are people who do not have enough to eat, have trouble affording energy bills to heat their homes, have inadequate homes, or lots of other “issues”, then the economy isn’t working properly.

I do not know of an easy fix for this, but we do need to start looking into fixing things so that we all benefit from the wealth created by the economy. And in such a way that the wealth isn’t frittered away. It doesn’t mean total equality – those who contribute more should get more out of the system, but we have a broken system at the moment that doesn’t actually reward those who contribute more properly – it only rewards the wealth creators.

Now genuine wealth creators do deserve to be rewarded more than those who do not contribute so much. But they should not be rewarded excessively when everyone else is suffering (to a greater or lesser extent).

One thing that might help is a way of taxing bonuses and golden parachutes in a way that takes away money from those who just manage to get good contracts, but leaves more money with those who really increase wealth. If for example, we start with a base rate of 50% tax on all bonuses and golden parachutes greater than the average yearly salary. That percentage goes up to penalise those who have not increased profits and have lost jobs, over the last 10 years, and the percentage goes down to those who have created jobs and increased profits over the last 10 years.

Oh! And one last thing. Not all rich people are greedy pigs. On a day when Jimmy Saville has died, it is well to remember that he gave away 9/10ths of his pretty large income.

Arundel Again

 Photography  No Responses »
Oct 242011
 

Back to the same old place again … the big change this time was walking around the other way :-

#1: Downhill

Downhill

If you can’t tell, this is looking down one of the steeper parts of the path.

2: Autumn Leaves

Autumn Leaves

Yes, yes. Autumn leaves should be in colour. But in fact the lighting was sort of flat so it wouldn’t be that impressive in colour (either).

3: The Garden Shed

Garden Shed

I’m sure it’s not really a garden shed, but that building you can see in this image is not the real castle so it could be a garden shed. A big one.

Gaddafi’s Death

 Politics  No Responses »
Oct 242011
 

Our old friend Gaddafi was killed sometime on the 20th October, and due to doubts over how he died, there are some who are concerned with how the future of Libya will suffer because he was potentially lynched. These concerns are ridiculous.

Of course we can agree that a lynching (or a summary execution … or whatever it was) is bad, and that a properly conducted trial would be better. But it will hardly have a great effect on the future of Libya. However Gaddafi was killed, it would seem that if the killing was done by the militia in an inappropriate way, it was almost certainly done against the wishes of the NTC.

And even if it were the case that the NTC let it be known they wouldn’t be too upset if Gaddafi kept falling down steps until he was no longer able to get up again, it wouldn’t be the end of the world. Or even a sign that Libya is going to slip into a barbarous disregard for human rights.

Gaddafi was a special case – there are many Libyans with a personal reason to celebrate at Gaddafi’s death. Enough so that the percentage of those of us who believe that taking justice into our own hands is justified would cover enough people that it was pretty likely that Gaddafi would have met a bullet in the back of the head. That is not a good thing of course.

But as far as I can see, Libya does not appear to be going through the kind of convulsions that happen when neighbour starts lynching neighbour. There are plenty of people in Libya who supported the old regime, and it does not seem to be a widespread activity to put said people up against a wall. Which is a good sign – no matter what happened to Gaddafi, it would seem that Libyans want the kind of society where justice takes precedence over lynch mobs.

grub rescue Error : the symbol ‘grub_xputs’ not found.

 Linux, Working Notes  No Responses »
Oct 202011
 

So there I was, installing a Linux distribution on my new laptop. Got to the end of the installation when it refused to install grub in the master boot record. Opted to try another partition, and rebooted. At which point the infamous error “Error: the symbol ‘grub_xputs’ not found” was shown with a “grub rescue” prompt.

At which point I had a laptop that wouldn’t boot of course.

To cut a long story short, because it’s only the fix I’m interested in recording for posterity, I sorted this out by booting off an emergency USB stick (unetbootin is a good tool for writing one … if you have a working system). Once booted, I setup an environment where chroot would function well. This is basically where you start a shell whose root directory is a directory under the normal root directory. This allows commands to be run almost as if the non-bootable system was booted.

mount /dev/sda5 /mnt # Mount the root filesystem of the unbootable system under /mnt
mount /dev/sda1 /mnt/boot # And the /boot filesystem
mount -o bind /proc /mnt/proc
mount -o bind /dev /mnt/dev
mount -o bind /sys /mnt/sys
chroot /mnt

Once that is done, there are quite a few things that can be done to repair a broken system, but I just needed to re-install grub to the MBR of /dev/sda :-

grub-install /dev/sda

Once that was done, everything booted fine.

Of course all that comes with the experience of a lot of time with Linux. Those who have not used it since the 1990s will not be as lucky, but there’s a few key points there :-

  1. Don’t panic. Just because it won’t boot doesn’t mean everything is lost.
  2. Write down the error message exactly as it appears on screen. A small mistake here can make searching for the error almost impossible.
  3. Get a rescue USB stick. Ideally before you break a system, but afterwards is usually possible even if you don’t have another working system – you have friends, or there are ways to write a USB stick at work.
  4. Search the Internet for the problem. You may have to spend quite a while reading other people’s problems that may or may not relate to your problem. You may have to improve your search methodology. Putting the error message in quotes is usually a good method.
  5. And if you find a solution to your problem online, check the date of the solution. Something that worked 5 years ago may not be the best solution today. And that applies to this page just as much as any other.
Oh! And to those who would jump and down screaming about this wouldn’t happen with Windows or OSX, please grow up. Such problems occur with any operating system – and I’ve seen them.
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