ostore.apps.test
Class TrafficGenerator
java.lang.Object
|
+--ostore.apps.test.TrafficGenerator
- All Implemented Interfaces:
- EventHandlerIF, ProfilableIF, SingleThreadedEventHandlerIF
- public class TrafficGenerator
- extends Object
- implements SingleThreadedEventHandlerIF, EventHandlerIF, ProfilableIF
The TrafficGenerator is a small, simple client that
provides a stream of random OceanStore traffic. This traffic
can act as a small, incomplete test vector for OceanStore.
Overview of Operation of :
After the TrafficGenerator has received the
StagesInitializedSignal, it dispatches a request to
create the first data object. When the response for that request
or any future request is returned, the
TrafficGenerator creates zero or more new requests
by the following procedure. If there are no more outstanding
requests, the TrafficGenerator creates and
dispatches another request to prevent the system from quiescing.
If the TrafficGenerator still has outstanding
requests, it chooses a random number and compares that against a
user-provided threshold. If the random number is below the
threshold, the TrafficGenerator creates and
dispatches another request. After dispatching a request, if the
number of outstanding requests has not yet reached the maximum
number of outstanding permitted, the
TrafficGenerator will repeat the process using a new
random number.
The type of traffic created is determined by an array of random
number generators and parameters defined in the initialization
scripts. If all requested objects have not yet been created, the
TrafficGenerator determines randomly whether to
submit a create object request or a read/write request. If it
has chosen to send a read/write request, it selects a random data
object and determines whether to send a read request or a write
request. (Obviously, if the data object contains no data, it
will first submit an append request.) If it has chosen to send a
read request, it creates a read request based on the read
distribution parameters provided in the initialization scripts
and dispatches the request. If it has chosen to send a write
request, the TrafficGenerator the randomly
determines whether to send an append update or a replace update.
The TrafficGenerator then creates the update based
on the write distribution parameters provided in the
initialization scripts and dispatches the request.
Initialization Parameters: The behavior of the
TrafficGenerator can be controlled by a large number
initialization parameters. These parameters and their result are
described below.
- NumObjects
- The number of data objects to create.
- MaxObjectSize
- The maximum allowed size of a data object. After reaching
the maximum size, all other updates to that object will be
replace updates.
- TotalTraffic
- The number of requests to dispatch. After sending this
number of requests and receiving their responses, the stage will
terminate with an exit code of success.
- MaxTrafficRate
- The maximum number of outstanding requests permitted.
- TrafficRate
- An integer, 0 <=
TrafficRate <= 100, that
represents the probability that the TrafficGenerator
will submit another request after receiving a response to an
earlier request. If there are no more outstanding requests, a
new request will be dispatched regardless of the value of
TrafficRate, and if there are
MaxTraffic outstanding requests, a new request will
not be dispatched. Note, that this parameter is most effective
in the range 40 < TrafficRate 60. If the value of
TrafficRate is much smaller, the amount of
outstanding traffic is almost always very small; if the value of
TrafficRate is much greater, the amount of
outstanding traffic is almost always MaxTraffic.
- CreateRate
- An integer, 0 <=
CreateRate <= 100, that
represents the probability that the TrafficGenerator
will, after it has decided to submit a request, create and
dispatch a create object request. For example, if
CreateRate is set to 3, there is a 3% chance that a
create object request will be dispatched. After all objects have
been create, the CreateRate is no longer
relavant.
- ReadRate
- An integer, 0 <=
ReadRate <= 100, that
represents the probability that the TrafficGenerator
will, after it has decided to submit a read/update request, create
and dispatch a read request. For example, if
ReadRate is set to 50, there is a 50% chance that a
read request will be dispatched. Note, if ReadRate is
set to 100, each data object will be updated exactly once (to
append data into the empty object); all other requests will be
for reads.
- AppendRate
- An integer, 0 <=
AppendRate <= 100, that
represents the probability that the TrafficGenerator
will, after it has decided to submit an update request, create
and dispatch an append update request. For example, if
AppendRate is set to 65, there is a 65% chance that
an append update reuqest will be dispatched. Note, if
AppendRate is set to 0, each data object will be the
object of exactly one append update request (to append data into
the empty object); all other update requests will be replace
update requests.
- RP_Pkeyfile
- The full path to a file storing a representation of the
responsible party's public key.
- Principal_Pkeyfile
- The full path to a file storing a representation of the
principal's public key.
- Principal_Skeyfile
- The full path to a file storing a representation of the
principal's private (secret) key.
- RandomSeed
- An integer used to seed the random number generator which
seeds other random number generators.
- MinTrafficDelay
- An integer, 0 <=
MinTrafficDelay <=
MaxTrafficDelay, that is the minimum delay in
milliseconds between traffic events. The traffic delay is
uniformly distributed between MinTrafficDelay and
MaxTrafficDelay. The default value of
MinTrafficDelay is 0 so that events are dispatched
as soon as they are created.
- MaxTrafficDelay
- An integer, 0 <=
MinTrafficDelay <=
MaxTrafficDelay, that is the maximum delay in
milliseconds between traffic events. The traffic delay is
uniformly distributed between MinTrafficDelay and
MaxTrafficDelay. The default value of
MaxTrafficDelay is 0 so that events are dispatched
as soon as they are created.
- Version:
- $Id: TrafficGenerator.java,v 1.14 2004/05/13 19:42:42 hweather Exp $
- Author:
- Patrick R. Eaton
| Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
TrafficGenerator
public TrafficGenerator()
handleEvent
public void handleEvent(QueueElementIF element)
throws EventHandlerException
- Specified by:
handleEvent in interface EventHandlerIF
EventHandlerException
handleEvents
public void handleEvents(QueueElementIF[] element_array)
throws EventHandlerException
- Specified by:
handleEvents in interface EventHandlerIF
EventHandlerException
init
public void init(ConfigDataIF config)
throws Exception
- Specified by:
init in interface EventHandlerIF
Exception
destroy
public void destroy()
throws Exception
- Specified by:
destroy in interface EventHandlerIF
Exception
profileSize
public int profileSize()
- Specified by:
profileSize in interface ProfilableIF