Recent changes to bugs

GridSim [Want to change scheduling]

Faisal Haroon — Wed, 26 Feb 2014 13:41:37 -0000

Hi,

i donot know where to join gridsim discussion forum thats why i put my query here.

i am working on my MS thesis. kindly guide me how i can change schedule i.e. now its using FCFS and i want to change with shortest job first. kindly suggest me how to do this.
i have reviewed the basic 10 examples of grid sim.

Regards,

Faisal

GridSim version

Anonymous — Wed, 20 Feb 2008 09:57:43 -0000

In the GridSim.java there was left old code:

public static void startGridSimulation() throws NullPointerException
{
System.out.println("Starting GridSim version 4.0");
...

which result in little confusing outputs - I was not sure if I am using GridSim 4.0 or new 4.1 version :-)

Regards,

Dalibor Klusacek
xklusac@fi.muni.cz

Gridlet history is created regardless the value of traceFlag

Marcos Dias de Assuncao — Tue, 15 Jan 2008 03:32:44 -0000

This is a bug in the Workload class. When using this class to read a workload trace and create Gridlets, the Gridlets are created with the record history option set to true, regardless the value passed as traceFlag in the GridSim.init() methods.

At workload class contains:
protected void submitGridlet(int id, long submitTime,
int runTime, int numProc) {
// create the gridlet
int len = runTime * rating_; // calculate a job length for each PE
Gridlet gl = new Gridlet(id, len, size_, size_);
...
}

While the Gridlet class contains:

public Gridlet(int gridletID, double gridletLength,
long gridletFileSize, long gridletOutputSize) {
this(gridletID, gridletLength, gridletFileSize, gridletOutputSize, 0);
this.record_ = true;
}

The history of a Gridlet is stored in an attribute of StringBuffer type. Once the simulation is complete, each history has a size of approximately 670 bytes. This becomes a memory bottleneck for simulations with a large number of jobs. As GridSim is supposed to be a Grid simulator, that scenario is not unlikely.

Therefore, Workload class should read the value of traceFlag and generate the history of Gridlets only when the user requests it.

Wrong value is returned

Anonymous — Thu, 04 Oct 2007 18:51:44 -0000

The method gridsim.Accumulator.getStandardDeviation() returns the value of variance, not a standard deviation. It would be preferable to rename this method to "getVariance()" and implement the "getStandardDeviation()" as:

public double getStandardDeviation() {
return Math.sqrt(getVariance());
}

Stanislaw Szczepanowski

Size of a reply to a query for free/busy times

Marcos Dias de Assuncao — Sat, 22 Sep 2007 02:10:43 -0000

The method replyTimeReservation(int, int, ArrayList, double) of the class ARPolicy may not provide the proper size of a reply to query for free or busy periods.

The size is calculated correctly in the following snippet of code:

int size = SIZE;
if (result != null) {
size = (4*8) + result.size(); // 3 longs + array size + overheads
}

However, the reply is sent in the following manner:

super.sim_schedule(super.outputPort_,0,GridSimTags.RETURN_AR_QUERY_TIME, new IO_data(array, SIZE, destID) );

Therefore, if the result is not null, the message size provided will be incorrect.

Regards,

Marcos