• SSL/TLS sockets programming using openssl and polarssl

    I was trying to do some modifications to mongoose http server to use polarssl, to do that I tried to understand openssl and polarssl libraries, for that I wrote some example client/server programs, See https://github.com/CloudFundoo/SSL-TLS-clientserver, may be useful. To compile this with libssl, first install openssl(or libssl) library, dev package...


  • DRAM errors, cosmic rays and bit flips

    Take a look at these articles, it will give you a good idea of memory errors and the use of ECC hardware. These bit flips are easy say but hard to prove, bugs in the system. The first articles shows when page cache in Linux can be evil. Attack of...


  • I/O Multiplexing in Linux : Part 1

    There is lot of discussion going on I/O multiplexing in Linux, select (), poll () and epoll () are the Linux mechanisms for that. I looked at the kernel implementation in order to better understand that, this may help you guys also. We will start with examples of how to...


  • Inside select() call macros

    I was looking at the IO multiplexing calls for writing an IO library, select() has some macros for setting, clearing the file descriptors in file descriptor sets. While looking a for a method to optimize the walk through fd sets, i looked at the implementation of those macros. Let’s go...


  • Distributed Hash Tables and Consistent Hashing

    DHT(Distributed Hash Table) is one of the fundamental algorithms used in distributed scalable systems; it is used in web caching, P2P systems, distributed file systems etc. First step in understanding DHT is Hash Tables. Hash tables need key, value and a hash function, where hash function maps the key to...


  • Minor Page faults and dynamic memory allocation in Linux

    There is a very good paper written by Philip Ezolt, this paper takes the reader for a step by step analysis of a problem where malloc is causing large number of minor page faults. If you want to understand what is written here, you must read that paper. In that...


  • Open Source Ecosystem for Cloud

    Here is a Good presentation from Citrix guy, its lists many of the open source projects required for building a cloud. Worth a look! Delivering IaaS with Open Source Software