4 LWF file format

The LWF (Lease Workload Format) describes a workload of leases that can be used by Haizea when running in simulation mode. In this workload, the starting time is 00:00:00:00, and all times are specified relative to that starting time. For example, an AR lease requested to start at 00:01:00:00 starts one hour after the start of the workload. Each lease also has an arrival time, the time at which the lease is submitted to Haizea.

The root element of an LWF file is the <lease-workload> element:

<lease-workload name="...">

This element has a single attribute name, with the name of this workload. The <description> child element can be used to provide a longer description of the workload. The <site> element is used to specify the site the workload is meant to be run on, and the <lease-request> element contains the actual lease requests. Each <lease> element is wrapped inside a <lease-request> element:

<lease-request arrival="...">
  <realduration time="..."/>
  <lease ...>

This element has an attribute arrival indicating when the lease is submitted to Haizea. It can also have an optional <realduration> child element specifying the real duration of the lease. In many systems, users request resources for a period of time, but relinquish the resources earlier. When simulating workloads, it is important to take this information into account, since the simulator must stop the lease at the end of that ``real duration'', not at the end of the full requested duration. Note that, if a <realduration>, Haizea will still schedule the lease assuming it is going to use its full requested duration (since, like a non-simulated scheduler, it can't assume to have a priori knowledge of when the lease will really end), but the simulator will generate an event indicating the lease has ended prematurely when its ``real duration'' has elapsed.

Borja Sotomayor 2009-12-17