Pollution Efficiency of Alternative Fuel Cars

November 25th, 2014

Every now and then, when discussing EVs (electric vehicles) or other alternative fuel cars(1), that offer basically zero pollution (in the form of green house gases and other poisonous gases) someone always raises the argument that these cars just “move the pollution upstream” to the electric power plants and you are still polluting just the same.

But this argument only works if the power production “upstream” really is polluting as much as an onboard gas engine – which really sounds weird to me, because as you increase the success of the engine – from something that had to be small enough to fit in a car to something that basically only had the limit of required to be cost effective – surely you can have large efficiency gains, even if burning the same fuel?

So here are some numbers:

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  1. like the new “hydrogen powered” cars []

Script day – Amazon AWS Signature Version 4 With Bash

November 19th, 2014

As anyone who works with the Amazon Web Services API knows, when you submit requests to an AWS service you need to sign the request with your secret key – in order to authenticate your account. The AWS signing process has changed through the years – an earlier version (I think version 1) I implemented in a previous blog post: upload files to Amazon S3 using Bash, with new APIs and newer versions of existing APIs opt in to use the newer signing process.

The current most up to date version of the signing process is known as Signature Version 4 Signing Process and is quite complex, but recently I had the need to use an AWS API that requires requests to be signed using the version 4 process in a bash script(1), so it was time to dust off the old scripting skills and see if I can get this much much much more elaborate signing process to work in bash – and (maybe) surprisingly it is quite doable.

With no further ado, here is the code:

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  1. I’m trying to use SQS to send change notifications from a FreeBSD jail running on a FreeNAS server – a place were I’m uncomfortable installing the AWS CLI tool or the SDK. This also help explains all the FreeBSD compatibility written into the code []

הלקוח צודק, גם כשהוא מעצבן

August 10th, 2014

English: GSM Micro SIM card vs. GSM Mini SIM card

ניגשתי היום לנקודת שרות של סלקום בשביל לשחזר את כרטיס ה-SIM של הטלפון שאיבדתי (את הכרטיס, לא את הטלפון), וכשאיש השרות שאל אותי איזה סוג כרטיס אני צריך, עניתי לא בפשטות “הרגיל – מיני SIM”. מה שהוביל לויכוח האם קיים דבר כזה שנקרא “Mini-SIM” (רמז: קיים, זה מה שיש ברוב הטלפונים).

 

שזה כנראה היה טעות מצידי, כי איש השרות א) לא מבין במוצר שהוא מוכר (שזה לא מקרה מיוחד), אבל ב) משוכנע ש(חוסר) הידע שלו הוא הדבר הנכון ו-ג) מאוד לא סלחני לאנשים שמנסים להסביר לו שהוא טועה – מה שגרם לכך שקיבלתי שרות ממש גרוע ויחס מזלזל.

 

GNOME 3 Fails As A Desktop Environment

August 6th, 2014

Because if you don’t like exactly 100% what the GNOME developers think the desktop should look like, then too bad, you’d just have to suffer.

In addition to really annoying misbehaviors that I doubt anyone could justify (like the evolution color problem), here are the list of things that cause me to hate GNOME and will eventually cause me to reinstall KDE.

Full disclosure: I’m normally a KDE user and have been trying the latest GNOME using Fedora 21 pre-release. I expect that some of the things I mention below are bugs that will be fixed in time for the public release, and if so feel free to point them out. Also, I’m aware that some of the issues I have can be “fixed” by installing the GNOME Tweak tool or editing the dconf (the GNOME “registry”), but I don’t feel this is a valid way to build software – “if you want it to not be painful, you should be an advanced user”. Did I mention I love KDE?

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Why Microsoft Will Not Extend Windows 7 End-Of-Life

July 13th, 2014

[This is mostly a summary of a discussion on Google Plus, that you can find here]

Recap: The world (or at least clueless tech journalists) was surprised to learn (once they bothered to look it up) that Microsoft will not extends Windows 7 end of “mainstream support” – which is scheduled for January 2015 (about 6 months from now). This was all planned way in advance – Microsoft basically committed to end “mainstream support” in 2015 by not releasing any service pack for Windows 7 since the beginning of 2010, instead they want people to move to the next version of their software. In most normal software markets, this is a no-brainer – who have heard of a Macintosh user still clinging to Mac OS X 10.7? or an Adobe Photoshop user who refuses to upgrade past CS3? But instead you now hear calls for Microsoft to extends Windows 7 an artificial life line, like it did with XP.

And here’s why XP will never happen again:

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מתכון: עוף חמוץ מתוק (לא בצבע ורוד)

July 10th, 2014

הנה מתכון פשוט לאסקלופ(1) עוף, ברוטב לא בסגנון סיני או בצבע ורוד או משהו כזה, אבל כן בטעם חמוץ מתקתק. הרכיבים לארבע מנות.

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  1. כמו שניצל, אבל בלי הציפוי []

Microsoft vs. No-IP and the failure of the US legal system

July 9th, 2014

There is one thing that really troubled me about the Microsoft dynamic DNS fiasco that no one seems to talk about, which I really wanted to raise, but first here’s a short recap for those not in the know: Microsoft “cyber-security” department convinced a US federal court to issue an order to transfer 22 internet domains owned by the popular No-IP dynamic DNS service into their custody, in an attempt to remove specific hosts under those domains that are supposedly used as malware control centers.

The issue I have is very simple – under what conditions can it be possible for a private company, to ask a court to transfer ownership of a property from another private company? This sounds seriously like private policing and somehow it is endorsed by the judicial system ?!? Under what authority can something like this be allowed?

This situation is massively more grievous because the court order was given “ex-parte” – legalese for “without the other party appearing to defend itself”, but even if everything was over the table and in the clear, and the defending lawyer incredibly incompetent, what kind of argument a private entity can offer to get a court to simply transfer control of another private entity?(1).


  1. except obviously arguing that the property was stolen, which is clearly not the case []

Code Spaces break-in lessons: using your infrastructure provider for backup is a single point of failure

June 30th, 2014

Summary of the events of the Code Space break-in: Code Spaces was hosting their services on Amazon Web Services VPS infrastructure. An attacker managed to gain access to their AWS administration console account and after his demands for ransom were not answered, proceeded to delete all the data in the account.

The disaster recovery plan for Code Spaces was based on having machine images and data backups stored in AWS, everything was gone, and Code Spaces basically had to shutdown.

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Why I hate 4K displays

June 18th, 2014

Well, I don’t have very high resolution displays at all (you might call them UHD displays?), but the name “4K” is really stupid – so please stop using it.

What is it 4000 of anyway? Can anyone tell me? Hint – no it doesn’t have 4000 pixels, nor 4000 scan lines or 4000 anything or event anything else that is divisible by 4000. Although the horizontal resolution is almost 4000 (actuallly 3840 pixels wide), and while Wikipedia will have you believe that is the reason for the name, it is not so.

No, the reason is so much stupider than that: the name “4K” is because “4K displays” are 4 times larger (in pixel count) than 1080p displays (1080 being about 1K). This is so stupid, because while UHD displays do indeed have 4 times the pixels of a 1080p (“1K”) display, the 1080 in the number does not relate to the number of pixels – it is the number of scan lines in the picture – of which a UHD display has only twice as much. But “2K” just doesn’t have the right ring to it… so, the branding masters made do with what they have. Sooooo stupid…

What to do when your virtual private server is really slow

June 8th, 2014

Ok, this is not a real solution for all types of problems – just a tip, that worked for me today, to try out if you can’t figure out what the problem is.

I’m running a VM on Amazon EC2, and looking at top, I saw that most of the CPU time was spent either in “steal/guest” or “IRQ“. Now steal/guest is kernel speak for “I wanted to allocate some CPU time for progams, but the hypervisor stole it” – which is not surprising on a a virtualization solution, but if it happens all the time then that means that your physical host is constantly loaded by other VMs that take as much CPU time as they can. The second item “IRQ” is time the kernel spends at handling interrupt requests from the hardware. This shouldn’t consume a significant amount of time unless the hardware has a problem – another good indication that you want to move your VPS to another physical host.

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