Amazon Web Services X1 Instances

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Aws  released the x1 instances. The new instance type offers 128 virtual cores and  about 2 tb of RAM.

I will never stop to be susprised of this job, i still feel excited reading this stuff. I feel like my son when he sees a new toy, he just wants to play with it.

The new instance is designed to be used in big data analysis and in particular for sap hana.

I suggest to check the article, it is worth to be read.

https://aws.amazon.com/blogs/aws/x1-instances-for-ec2-ready-for-your-memory-intensive-workloads/

Besides. Aws released a new guide on how to implement a new sap hana environment in a vpc in one hour.  If i am not mistaking, it has been just released https://s3.amazonaws.com/quickstart-reference/sap/hana/latest/doc/SAP+HANA+Quick+Start.pdf

Talking to a friend of mine, he asked “yes, nice, but how much will it cost?”. It is a good question but I do believe that the point in this case, is not “how much it will cost” but it is about making possible something that it is usually impossible in most of the traditional datacenters.

Well done AWS, once again.

 

Redhat Enterprise Linux it’s free now! (for development scope!)

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From Yesterday, Redhat Enterprise Linux is free for usage for developers!

This is a incredible news for anyone having worked with the best enterprise Linux distro.

This is an evident countermeasure against Ubuntu and Amazon Linux, well done Redhat!

No-Cost RHEL Developer Subscription now available

In simple words, I am sorry CENTOS 🙂 I loved you but it’s over

Dropbox Magic Pocket

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Dropbox, one of the biggest AWS installation, implemented its own storage solution

The reading is very interesting and highlights what is under the hood of this fantastic service.

 

Actually dropbox has impressive numbers. They currently have 500 PB of data, very few companies in the world have such a massive amount of storage.

 

https://blogs.dropbox.com/tech/2016/03/magic-pocket-infrastructure/

Stackoverflow 2016 architecture

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The linked article provides a deep analysis of the stackoverflow architecture.

They use 11 IIS servers, 4 SQL Servers, Redis, Elasticsearch and HA Proxy in front of the web heads.

http://nickcraver.com/blog/2016/02/17/stack-overflow-the-architecture-2016-edition/

It is a very interesting article. They handle a massive number of hits every day, 209,420,973 hits. with a bunch of servers

It is rather a surprise the fact they are not using any cloud solution, would be interesting to know why.

Devops, Busting 6 myths about DevOps

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Many people around talk about Devops like if it is the end of any rule or standard techniques.

It is like ITIL should not be adopted anymore, security is an option or operations team are meaningless (it would be called DEV, without OPS I guess).

https://opensource.com/business/15/4/6-common-devops-myths

In my humble opinion, Devops was embraced by 777 developers which have finally an excuse to bypass every common sense rule.

As usual, these 777 people prefer to take shortcuts instead of doing things in the right way.

I do believe that DevOps is the way to go. But deveops does not mean caos and entropy everywhere.

 

PHP Don’t know how to define struct flock on this system

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Introduction

While compiling a custom version of PHP (5.6.14) on a Redhat 6.5 I got the following error:

configure: error: Don’t know how to define struct flock on this system, set –enable-opcache=no

Looking around on the net didn’t find a lot of information about it.

 

Solution

Using a bit of logic and understanding that flock is the file locking mechanism at file system level, I thought about a missing devel header in my system about file system locking mechanism.

File lock is implemented by libtool package

yum search libtool
============================================================================================== N/S Matched: libtool ===============================================================================================
libtool-ltdl.i686 : Runtime libraries for GNU Libtool Dynamic Module Loader
libtool-ltdl.x86_64 : Runtime libraries for GNU Libtool Dynamic Module Loader
libtool-ltdl-devel.i686 : Tools needed for development using the GNU Libtool Dynamic Module Loader
libtool-ltdl-devel.x86_64 : Tools needed for development using the GNU Libtool Dynamic Module Loader
libtool.x86_64 : The GNU Portable Library Tool

 

Then, by just doing a simple installation of the required package (libtool-ltdl-devel) solved the issue and PHP configure process completed like a charm.

yum install libtool-ltdl-devel

I decided to document it since I noticed that many people went for the easy solution and disabled the opcache support. This has serious performance penalties and IMHO should be avoided at all costs.

 

CppCon 2015: Bjarne Stroustrup “Writing Good C++14”

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Introduction

This is a very good talk from Stroustrup about good rules to be followed when writing modern C++ applications.

The first 25 minutes are generic about teams coding guidelines which I personally believe apply to any programming language.

The rest of the video is very valuable, in particular about different approaches to avoid typical C++ problems. In particular I liked the way they handle owners pointers and avoidance of dangling pointers.

 

 

Data structures considerations in concurrency situations

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This short article is worth for reading. It provides useful considerations about typical data structures (linked lists, Balanced Search Trees) in multi concurrency environments.

People often underestimates the concurrency requirements of the data structure they use. This article (basic) provides useful information.

Deadlock is our enemy!

http://www.drdobbs.com/parallel/choose-concurrency-friendly-data-structu/208801371?pgno=1