= How to use Hive-3.4 for optimization =
This page gives you instructions how to use HeuristicLab.Hive-3.4 for optimization problems.

Hive gives you the possibility to execute independent algorithms in parallel. It distributes those algorithms as jobs to a network of slaves which execute them and post back the results. Hive performs best if there is a large number of jobs which have long executen-times. Also if limited memory is a issue on a local PC, Hive can be an advantage since it can decide to run the jobs only on machines with enough memory (like the blade server nodes).

The following steps are required to run a Hive Experiment:

 1. Download the most recent plugins for the Hive Experiment Manager Client (source:/branches/HeuristicLab.Hive-3.4/binaries/HeuristicLab.Hive.ExperimentManager-3.4.zip)
 1. Copy plugins to HeuristicLab directory (usually "C:\Program Files\HeuristicLab 3.3\")
  * Notice that you also need to copy ''"HeuristicLab 3.3.exe.config"'' and overwrite the existing one. This is no problem as long as you haven't made any modifications in the config file. If you have your own version of the config file see [wiki:HiveHowTosUseHiveForOptimization#Mergingconfigurationfiles Merging Configuration Files]. 
 1. Start HeuristicLab Optimizer
 1. Go to ''Services > Set Username / Password'' and enter your credentials
  * You need a user and proper privileges as ''Hive User'' on the server (which is services.heuristiclab.com). These privileges can be requested from S. Wagner.
 1. Go to ''Services > Hive > Experiment Manager''. Now the list of your Hive Experiments is updated. The experiments are grouped into the owners of the experiments.
 1. Click the plus symbol on top of the list to create a new ''Hive Experiment'' \\ [[Image(HiveExperiment.png, width=700)]] \\
 1. Now you need to specify which experiment should be executed on the Hive. You can either
  * ... create a new experiment by clicking the ''"plus symbol"''.
  * ... move an existing experiment onto the view via drag and drop.
 1. After having created or loaded an experiment you can click ''"Modify Optimizer"'' in the details view to modify it.
 1. Each algorithm (also experiments and batch-runs) represent one job. \\ [[Image(JobConfiguration.png, width=800)]] \\
 1. Important configurations are:
  * !CoresNeeded: (default: 1) Specifies how many cores will be reserved for this job on the executing machine. If you know the algorithm corresponding to this job will use multiple threads for computation, increase this number!
  * !MemoryNeeded: (default: 0) Specifies how much memory will be reserved for this job on the executing machine. It will only deployed on machines where the specified amount of memory is available.
  * Priority: (default: 0) This number affects the scheduling of the jobs. Higher numbers will be executed earlier. It is recommended to rank jobs with long execution-times to be executed earlier to avoid waiting for them in the end.
  * !ComputeInParallel: This flag is only available for experiments and batch-runs.
   * Experiment: (default: true) If true, a job will be created for each child-optimizer. If false the whole experiment will be executed as one job.
   * !BatchRun: (default: false) If true, a number of jobs will be created corresponding to the number of repetitions specified. If false the batch-run will be executed as one job.
 1. There are also some configurations available for the whole experiment:
   * !ResourceIds: You can specify on which machines your jobs should be executed. Those machines/resources are grouped into resource-groups. The top group is ''"HEAL"''. You can either enter the name of a group or the name of a specific machine.
   * !IsPrivileged: Jobs on Hive are executed in a secure sandboxed appdomain. However some plugins might require elevated privileges. If !IsPrivileged is checked, the jobs will be executed in a unrestricted appdomain. This option is only enabled if the user is allowed to (there is a role called ''"Hive !IsAllowedPrivileged"''). If you need this permission, please contact S. Wagner.
 1. After configuring the experiment you can hit ''"Start Experiment"'' and the jobs will be uploaded to the Hive. Hive will then take care of the distribution and execution of each job.
 1. While you keep the Hive Experiment Manager open, it will periodically fetch the status-updates of all jobs. When jobs are finished it will download the results automatically.
 1. You can also close HeuristicLab after uploading an ''Hive Experiment''. When you open the ''Hive Experiment Manager'' again, it will download you list of ''Hive Experiments'' and you can choose to download a specific one.
 1. Notice that when results are downloaded they will be reassembled into the original experiment. So after it finished you can again open the original experiment (''"Open Experiment"'') and see all the results in the !RunCollection as if it would have been executed locally.
  * Unfortunately it is not possible to preserve the ''!ResultsCollection'' of each algorithm when reassembling the experiment. However each ''!ResultsCollection'' is stored in the ''!RunsCollection'' anyway.

== Plugins ==
Hive automatically uses your local plugins. If they are not yet available on the server (because you are the first one to use this plugin), they are uploaded. When the jobs are executed, exactly those plugins are used.

Hive now also checks if you have modified a plugin. This means that you can modify plugins locally and use them in Hive, even though they have the same name and version as already existing plugins on the Hive server. 
To distinguish plugins, Hive uses checksums for comparing plugins and finding out if they are modified. 
If Hive notices that you have a modified assembly, it is automatically uploaded to the server. 

== Job-States == 
You can observe the states of all jobs in the ''"States"'' tab. It shows a gantt-chart of your jobs. This is very helpful to get a quick overview of the runtimes of all jobs: \\ [[Image(JobStates.png, width=700)]]

== Experiment Sharing ==
Experiments can be shared with Full or Read permissions. To do so, go to the ''Sharing'' tab and hit refresh. You will see the list of already granted permissions (empty at first -- the owner always has full permissions). Click add and enter the username of who you want to share with as well as the desired permission. After saving the permission, the other user will see that experiment in his experiment-list. Permissions can only be added to experiments which are already uploaded. Permission include the following actions:

 * Read: Download experiment, view jobs
 * Full: Control experiment and jobs, delete experiment, grant permissions to other users

\\ [[Image(Permissions.png, width=500)]]

== Statistics ==
To observe the current status and the workload there is a website which shows this information: http://services.heuristiclab.com/Hive-3.4/Status.aspx

== Merging configuration files ==
If you are building the trunk or your own HL-solution, the build-process will most likely overwrite ''"HeuristicLab 3.3.exe.config"'' in the target folder. This will overwrite all the Hive-specific configuration. To avoid this, you can use the !ConfigMerger to merge the Hive-specific configurations in your own build-process:

 1. Download config for !HiveExperimentManager (source:/branches/HeuristicLab.Hive-3.4/sources/HeuristicLab.Clients.Hive/3.4/ExperimentManagerOnly.config?format=txt)
 1. Copy the file to your own solution and rename it to ''"HeuristicLab.Hive.config"''
 1. Open properties of the file in Visual Studio and select ''"Copy if newer"'' under ''"Copy to Output Directory"''.
 1. Add the following line to your ''"!MergeConfigs.cmd"'' (if you have one, otherwise specify directly in post-build events):
  * {{{ConfigMerger "%SolutionDir%\HeuristicLab\3.3\%Outdir%\HeuristicLab.Hive.config" "HeuristicLab 3.3.exe.config"}}}