jeena/GGS-report
1
0
Fork 0
Code Issues Pull requests Projects Packages Wiki Activity Actions

added tests with bots

Browse source
This commit is contained in:
Jeena Paradies 2011-05-13 01:18:32 +02:00
parent 93052126e2
commit ddc755546a
1 changed files with 66 additions and 29 deletions
Download patch file Download diff file Expand all files Collapse all files

95
report.lyx
View file

@ -5727,7 +5727,7 @@ name "alg:exposing-erlang"
\end_inset \end_inset
An example of how Erlang functionality is exposed to a JavaScript GDL An example of how Erlang functionality is exposed to a JavaScript GDL VM.
\end_layout \end_layout
\end_inset \end_inset
@ -5869,19 +5869,6 @@ wide false
sideways false sideways false
status open status open
\begin_layout Plain Layout
\begin_inset Note Note
status open
\begin_layout Plain Layout
We should really do this graphic in EPS instead of PNG
\end_layout
\end_inset
\end_layout
\begin_layout Plain Layout \begin_layout Plain Layout
\begin_inset ERT \begin_inset ERT
status open status open
@ -5934,7 +5921,7 @@ name "fig:The-supervisor-structure"
\end_inset \end_inset
The supervisor structure of GGS The supervisor structure of the GGS
\end_layout \end_layout
\end_inset \end_inset
@ -5967,8 +5954,8 @@ key "Savor:1997:HSA:851010.856089"
\end_layout \end_layout
\begin_layout Standard \begin_layout Standard
There are several approaches to supervisor design in general (when not just There are several approaches to a supervisor design in general (when not
considering how they work in Erlang). just considering how they work in Erlang).
One common approach is to have the supervisor look in to the state of the One common approach is to have the supervisor look in to the state of the
process(es) it supervises, and let the supervisor makes decisions based process(es) it supervises, and let the supervisor makes decisions based
on this state. on this state.
@ -6032,26 +6019,34 @@ reference "fig:The-supervisor-structure"
\end_inset \end_inset
shows our two subsystems, the coordinator subsystem and the dispatcher shows the two subsystems, the coordinator subsystem and the dispatcher
subsystem. subsystem.
Since these two systems perform very different tasks they have been separated. Since these two systems perform very different tasks they have been separated.
Each subsystem has one worker process, the coordinator or the dispatcher. Each subsystem has one worker process, the coordinator or the dispatcher.
The worker process keeps a state which should not be lost on a crash. The worker process keeps a state which should not be lost in the event
of a crash.
\end_layout \end_layout
\begin_layout Standard \begin_layout Standard
A choice has been made to let faulty processes crash very easily when they The choice has been made to let faulty processes crash very easily when
receive bad data, or something unexpected happens. they receive bad data, or something unexpected happens.
The alternative to crashing would have been to try to fix this faulty data, The alternative to crashing would have been to try to fix this faulty data,
or to foresee the unexpected events. or to foresee the unexpected events.
This was not chosen since it is so simple to monitor and restart processes, This was not chosen since it is so simple to monitor and restart processes,
and so difficult to try to mend broken states. and difficult to try to mend broken states.
This approach is something widely deployed in the Erlang world, and developers This approach is something widely deployed in the Erlang world, and developers
are often encouraged to “Let it crash”. are often encouraged to “Let it crash”
\begin_inset CommandInset citation
LatexCommand citet
key "Armstrong03"
\end_inset
.
\end_layout \end_layout
\begin_layout Standard \begin_layout Standard
To prevent any data loss, the good state of the worker processes are stored To prevent any data loss, the good state of the worker processes is stored
in their respective backup processes. in their respective backup processes.
When a worker process (re)starts, the backup process is queried for any When a worker process (re)starts, the backup process is queried for any
previous state, if there is any, that state is loaded in to the worker previous state, if there is any, that state is loaded in to the worker
@ -6070,8 +6065,8 @@ The modules in the GGS are built to be capable of redundant operations.
By adding a backup process to sensitive processes, the state can be kept By adding a backup process to sensitive processes, the state can be kept
in the event of a crash. in the event of a crash.
The coordinator of the GGS prototype has this backup feature built in. The coordinator of the GGS prototype has this backup feature built in.
The coordinator passes state along to the backup process which keeps the The coordinator passes the state along to the backup process which keeps
data safe. the data safe.
If a crash occurs, the coordinator recovers the state from the backup process. If a crash occurs, the coordinator recovers the state from the backup process.
Figure Figure
\begin_inset CommandInset ref \begin_inset CommandInset ref
@ -6178,8 +6173,8 @@ Hot code replacement is a technique used to update systems while they are
running. running.
The main use of hot code replacement is in critical systems that require The main use of hot code replacement is in critical systems that require
low downtime, such as telecom systems. low downtime, such as telecom systems.
By using hot code replacement, systems can be able to achieve as high uptime By using hot code replacement, systems are able to achieve much longer
as possible and thus improving the reliability of the system. uptimes and thus improving the reliability of the system.
Code replacement is a feature that exists in Erlang which means that with Code replacement is a feature that exists in Erlang which means that with
some work it could be implemented into the GGS. some work it could be implemented into the GGS.
\end_layout \end_layout
@ -6189,7 +6184,7 @@ Testing
\end_layout \end_layout
\begin_layout Standard \begin_layout Standard
To make sure the GGS prototype adheres to the specification set, two different To make sure the GGS prototype adheres to the specification set, three different
approaches to software testing are used. approaches to software testing are used.
For simpler testing the GGS prototype uses unit tests. For simpler testing the GGS prototype uses unit tests.
Modules are tested on a high level, making sure each function in the module Modules are tested on a high level, making sure each function in the module
@ -6213,6 +6208,12 @@ citation needed
by QuickCheck tests. by QuickCheck tests.
\end_layout \end_layout
\begin_layout Standard
Finally to test the robustness of the prototype virtuall users, so called
bots are being used to simulate large amounts of players playing different
games simultanously.
\end_layout
\begin_layout Subsection \begin_layout Subsection
Unit testing Unit testing
\end_layout \end_layout
@ -6310,6 +6311,35 @@ QuickCheck was originally made for the programming language Haskell.
of testing concurrency within a program. of testing concurrency within a program.
\end_layout \end_layout
\begin_layout Subsection
Bots
\end_layout
\begin_layout Standard
In order to test the robustness of the GGS several different artificial
users, so called bots, have been implemented.
Each of this bots is programmed to play a game on the GGS as similar to
a real user as possible.
In the game Pong for example, the bot is watching the ball and moves its
pad up or down according what the position of the ball suggests.
For the GGS there is no difference in serving a real user or a bot.
\end_layout
\begin_layout Standard
With help of this method large amounts of players can be simulated playing
games on the GGS simultanously which is a good stress and concurrency test
for the overall system.
In section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:Statistics"
\end_inset
some of the statistical data retrieved with help of a whole network of
bots playing games is being presented.
\end_layout
\begin_layout Section \begin_layout Section
Case studies Case studies
\end_layout \end_layout
@ -7505,6 +7535,13 @@ In this chapter the results of the GGS prototype are presented and discussed.
\begin_layout Section \begin_layout Section
Statistics Statistics
\begin_inset CommandInset label
LatexCommand label
name "sec:Statistics"
\end_inset
\end_layout \end_layout
\begin_layout Standard \begin_layout Standard