Tag: measurement

  • Calculating Conditional Entropy in R

      conditionalEntropy <- function( graph ) {    # graph is a 2 or 3 column dataframe    if (ncol(graph) == 2 ) {       names(graph) <- c(“from”,”to”)       graph$weight <- 1    } else if (ncol(graph) == 3)       names(graph) <- c(“from”,”to”,”weight”)    max <- length(rle(paste(graph$from, graph$to))$values)  …

  • Load Volatility and Resource Planning for your Cloud

    Having your own cloud does not mean you are out of the resource planning business, but it does make the job a lot easier. If you collect the right data, with the application of some well understood statistical practices, you can break the work down into two different tasks: supporting workload volatility and resource planning.…

  • Measuring Load in the Cloud: Correcting for Seasonality

    Usage is over threshold, unleash the kraken!  Short run peaks are perfect for automated elasticity: the unpredictable consumption that we stay up late worrying about fulfilling.  But, short run peaks can be difficult to tease out from expected variation within the period: seasonality.  Using the open source statistical package R, we can separate and look…