BBC Climate Change Experiment FAQ
From Unofficial BOINC Wiki
[edit] What might I want to find out before starting?
[edit] Is it safe? - See BOINC FAQ: Security
[edit] How long will it take?
This depends on how fast your machine is and how often you switch it off. A 2.8 GHz P4 or Mac G5 machine will take about 20 weeks of continuous running. We recommend that you do not download the software if you only have your computer switched on for a couple of hours a week. The experiment will run when the screen is switched off.
This Transient Coupled Model should be more interesting as it is the first experiment that is meant to be realistic. Previous models have been more about finding out what the model does in response to some fairly extreme Forcings.
[edit] Why are the work units so big?
[edit] How big are the Work Units?
Compared to SETI@Home's and other Projects' Work Units, the Models are very big. A 2.8 GHz P4 machine running all the time will take about 20 weeks.
[edit] Couldn't they be made smaller?
SETI@Home timeslices its working units. BBC Climate Change Experiment Work Units are a Climate Model that runs for 160 model years. Trying to timeslice a model would make it very inefficient because you have to wait for the results of the first timeslice before the second timeslice can be started. So it doesn't help and you would have to move around a lot of large (possibly over a hundred MB) data files. Incidentally, when you really get into this project it is nice to see a whole model evolve rather than only part of it.
It is not practical to split a model into different areas because of the huge amount of communication between adjacent cells (3 times per timestep and over 4000000 timesteps per model). It isn't even practical to do this on a network drive let alone connecting only via the internet.
Thats enormous - does that mean I won't get credit for ages?
No you will get credit for each Trickle and there is a Trickle for each of the 160 model years. So you typically only have to wait for about a day to trickle on a fast PC. The stats updates are currently once per day.
Also you do not have to wait for someone else to validate your work.
So how long do these Trickles take and what are: a Model, a Checkpoint, a Trickle and a Timestep?
In BBC Climate Change Experiment the Work Units are a complete Climate Model. It stands alone, the project needs lots of slightly different models. The models are further subdivided into a Hindcast, a Forecast, Trickles, and Timesteps.
A Timestep represents a 1/2 hour of model time (not realtime) for the atmosphere and one hour for the ocean giving 72 timesteps in a model day. Every model year your model will Trickle (report), and there are 80 model years in each of the Hindcast 1920 to 2000 and the Forecast 2000 to 2080. A model year is 12 months of 30 days (not 365 days so you do get 30 Feb Dates). The model Checkpoints or saves its work every 432 Timesteps which is every 6 model days.
See also Climateprediction.net Size Table
Here's some rough performance numbers for a reasonably quick P4, using 1 logical cpu:
- Timestep = 2.7 Seconds
- Trickle/Model year = 19.5 hours
- Hindcast/Forecast = 65 Days
- Model = 130 days
You will not see credit in your stats until after the first stats update after your first trickle has been uploaded, then your credit will increase with each stats update where you have uploaded one or more Trickles. Stats updates are currently run only once per day.
More information on Sizes in the Climateprediction.net Size Tables.
[edit] What are the implications?
The BBC Climate Change Experiment Work Units are big but you get lots of Credit per Work Unit and you still get the Credit frequently because of the use of Trickle Reporting.
More worrying is that a computation error loses more work. What is the appropriate reaction to this? Complaining is unlikely to be useful as trying to make the Work Unit smaller has been considered and rejected as not practical. A better reaction would be to decide to make a backup from time to time so if you do suffer an error, you can recover without loosing too much work. If you want to do this, see How-To Backup BOINC.
If a model is lost, it will still generate useful information from data returned in the Trickles and the uploads once a decade.
Dave Frame (project co-ordinator) said:
Even if people make it half way, we can use their results. Ideally, we want them to make it all the way to 2080, with their own personal planet Earth, but we do understand that that may not always be possible. But for us, the period 1960-2000 is really important because that's the period when we can test the model you're running against reliable, global data (data is much sparser before about 1960 - there's much more data once satellites began keeping an eye on those regions in which people don't live/ships and planes don't travel through). So please do continue if you can. The BBC are going to run a show in early summer, but as scientists we're interested in a much more comprehensive analysis after that, as well. After the BBC series finishes, we'll keep analysing the data for several years after this (and add new experiments and models, too).
[edit] Is my computer up to the task?
The sugested minimum specification is a 1.6 GHz processor and 256MB of Ram. This isn't a hard limit, slower computers can run the software. However be aware that it is going to take a very long time. To work out how long you may want to look at the speed with which your computer is working through the model.
The usual measure of speed is Sec/TS, which is the number of seconds per timestep. You can find out this measure for your computer in two ways: Firstly they are shown on Trickle Reports which are viewable from Your Account, View computers, computerid. However you will need to have completed a model year before this shows up. The other alternative is to show graphics and Z to remove the BBC Side Bar. A Sec/TS should then be displayed.
The Sec/TS muliplied by 72 per model day, muliplied by 360 days per model year, multiplied by 160 model years in a complete model should give the number of CPU seconds. Divide this by 60, 60 and 24 to get the number of CPU days. This then need to be adjusted for the amount of time the computer will be on.
Results received back after a year will be accepted. If you know you will not be able to stick at it for as long as it takes, bear in mind that partially completed models are still useful (See Dave Frame's comments in question above and Question 5.1). Also if you upgrade your computer, it should be possible to continue your model on your next computer and that is likely to be faster so that it will take less time.
[edit] Do I need to be on-line all the time while the software runs?
Absolutely not. Once you have installed the software and registered with the project, you are free to disconnect from the internet.
As your computer reaches Trickle points, it will (if set to allow network access) automatically try to "trickle" a small amount of data which is used by the Project to track the progress of your experiment. If no network connection allowed or if unable to connect the Trickle will be stored up until the next successful communication. It is not essential to trickle data. However, an internet connection is required for the final upload of approximately 6 Megabytes of data (which can take about an hour on the slowest modems, for broadband/ADSL it should only require a few minutes) whenever you finish an experiment. Messages will appear in BOINC giving a large amount of detail about how this upload is progressing. The files are split up into five compressed "zip" files, and can be incrementally uploaded (i.e. you can pause/resume or exit/resume and so not have to download the entire file if an initial upload was interupted).
How is that possible; doesn't it need to communicate with other computers?
No your computer is doing a complete model on its own. This is why the work units have to be so big - the communication would have to be far too frequent. You cannot realistically do it even on a network drive let alone over an internet connection.
[edit] Can I suspend the experiment?
The BBC Climate Model should not interfere with the normal use of your computer. The first and easiest way to suspend the model is by a right click on the Boinc icon in the lower right desktop tray and checking 'Suspend'. This is functionally the same as using the Commands Menu.
Advanced users can suspend one Project at a time which can be done from the Projects Tab. There is a third suspend option on the Work Tab. It should not normally be used. If you use it, your Work Unit (a climate model) will be suspended and if you have more than one Work Unit downloaded, a different one will start. If you only have one model, a new model will be downloaded unless you have previously selected 'No New Work' and/or disabled network activity.
Alternatively, if you prefer, set your Preferences on the BBC Climate website, where you can choose to only run BOINC applications at certain times of the day or only after a period of inactivity (Note some people are finding that the run while inactive does not work).
BOINC is capable of "task switching" so running multiple BOINC Powered Projects allows each application a percentage of CPU time which you can set up for each project, so one project does not use up all the CPU time before finishing a Work Unit. You can also set projects to exit when preempted, or to remain in virtual memory (so as not to lose any work). However the BBC Climate Change Experiment Work Units are the most demanding of all, therefore it is best to assign one processor fully to a BBC model and share remaining projects on the other processor.
[edit] Can I uninstall the software?
If you wish to stop running BBC Climate Change Experiment under BOINC, simply "Detach" from the project. In Windows you can do this by right-clicking on climateprediction.net in the Projects Tab, and then selecting "Detach." In Linux and OSX open a terminal, navigate to the directory where BOINC is installed and type
./boinc* -detach http://climateprediction.net.
This should remove all BBC Climate Change Experiment project files, leaving you free to attach to other BOINC projects. If you want to uninstall BOINC, you should run the "Uninstaller" program from Add/Remove Programs in Windows, for Mac & Linux simply remove your BOINC directory or BOINC executable. We are grateful for any amount of time/energy you are willing to invest in this exciting project. However, please try to finish your experiment once you have downloaded it - do not download the package just to see what it looks like. This constraint is necessary to preserve the scientific validity of the project as partially completed experiments cannot currently be passed on or evaluated.
[edit] How-To and other issues with Getting Started
[edit] For "How-To", see Getting started with Climateprediction.net
[edit] Web proxies
If your internet connection uses a web proxy and you use the Windows BOINC graphical client, simply fill in your proxy settings from the "Settings / Proxy Server" menu selection. If you are running the Linux/Mac BOINC client, you will want to set the HTTP_PROXY environment variable to your proxy server. For other options (i.e. authenticated proxy User Name/password), please see the
[edit] Firewall Configuration
Note that if you have a firewall you should allow the BOINC client (boincmgr.exe and boinc.exe in Windows; boinc_* in Mac/Linux) to access Internet services on your computer. The client needs to communicate on port 80 (the basic HTTP port used by your web browser). All communication to BOINC servers is initiated by our software as with a web browser -- there are no open ports on your computer using this software!
If you are running a firewall make sure that BOINC has full browsing capability on port 80. Models have been known to crash when a firewall blocks access to a mirror server if it is configured to restrict BOINC access to named servers.
[edit] Proxy Server and Authentication
Win32 : For windows, click on "Setting" in the menu , and then "Proxy Server" to bring up the Proxy server configuration window.
Mac/Linux :
The Command-Line Version of the BOINC Client Software has optional environment variables and command-line options. See the article "BOINC Daemon - Command Line Interface - Command-Line Options" for more details.
[edit] About the Experiment
[edit] What does the Climateprediction.net Experiment do?
Details of the various stages of the experimental design of the project are available on the Strategy Page. This model is experiments 2. All the experiment 1 work has preiously been done through the Climateprediction.net (CPDN) Project.
The Transient Coupled Model or HADCM3L is the model that is used to carry out "Experiment 2" which involves both a Hindcast and a Forecast. This is the first time the models are meant to be realistic.
More information on the different models can be found in Climateprediction.net Models.
More information on the Climateprediction.net Science is here.
[edit] About running Climateprediction.net
[edit] How many experiments does the software do?
As many as you let it. The software runs a Model which completes one experiment, returning small sets of data from the model as it progresses. It then starts another, different Model. It goes around this loop until you choose to change to a different BOINC Project or uninstall BOINC entirely.
[edit] Disk Space
Each Model you run on your system will quickly grow to about 600MB of disk space while it's running. The model should delete the files once they are no longer needed so 600MB should be about the maximum requirement.
From time to time, the output files from the model are processed. They are converted from one format to another. This processing only takes a short time but during this period there is significant disk access and consequently your machine may become sluggish. If this is a problem, simply close down the whole package or just Suspend and restart it at a more convenient time.
In the Transient Coupled Model, there are uploads every 10 model years.
If models will not download, see Fixing download due to lack of disk space
[edit] Running BOINC as a Service
Open a DOS window and change directory to the one where you installed BOINC. Install the BOINC service by executing the command boinc_cli.exe -install Open the BOINC entry in the services control panel. Click on the Log On tab and make sure it is set as Local System account Open file explorer and go to your BOINC directory. Make sure the local system account has full access. Exit the BOINC GUI interface and remove it from any startup folder it is in. If you miss out this step the CLI service and the GUI will both start on the next boot. When the GUI starts it will generate a -144 error (shared memory file can't be created because it already exists) and your current Climateprediction.net Model might get trashed. Start the BOINC service (either from the services control panel or using the command net start boinc.
[edit] Is it safe to Defragment the Hard Disk?
Many people have found it safe to do so. Others have had problems. It is possible that if you a) Suspend BOINC or have BBC Climate Change Experiment suspended for another project to run) and b) Have 'Keep in memory while suspended' set to yes and c) Run a disk defragmentation process
then perhaps open file pointers will be pointing at the wrong place and cause the model to crash. It may therefore be safer to exit BOINC before doing a disk defragmentation process.
[edit] System Shutdown Procedure
If you are running BOINC Client Software on Windows make sure you exit the program before shutting down the system. The BOINC Client Software has no control over how Windows shuts things down, and you can get a corruption of the client_state.xml file which may cause the startup to fail when the system comes back up. The Command-Line Version seems to be safe when it's run as a service, but running:
net stop boinc
before shutting down will make sure.
The BOINC Client Software is a lot better than it used to be, but I still feel safer exiting the BOINC Client Software before a shutdown.
[edit] Command Line arguments
The Command-Line Version of the BOINC Client Software has optional environment variables and command-line options. See the article "BOINC Daemon - Command Line Interface - Command-Line Options" for more details.
[edit] Ready to Report???
This means that the core client is ready to report & will do so when next it contacts the scheduling server. Action to be taken : Leave it alone.
[edit] Should I install the BBC Program Manager if I am running BOINC?
You should not install both BOINC and the BBC Program Manager. The BBC Program Manager is an almost fully functioning version of BOINC. It installs to a different directory. So if you are running BOINC you should just attach to the project using your existing BOINC program Manager.
If you install the BBC Program Manager before realising it is just another BOINC project, your existing BOINC projects may appear to have disppeared. They are still there in a different directory. It is sensible to uninstall the BBC Program Manager and reinstall BOINC then attach to the project using BOINC.
[edit] Should I upgrade to BOINC from BBC Program Manager?
Probably not necessary. The BBC Program Manager is an almost fully functioning version of BOINC. Remember that it is installed to a different directory. So if project xyz@home requires an upgraded version of BOINC, that should be OK to install but remember that you will need to install it to your Climate Change Experiment Folder rather than the default BOINC folder.
[edit] Graphics Compatibility
The visualization requires a graphics card that has OpenGL support. To test your card for GL compliance, download the OpenGL extensions viewer from here. Run the standard base install and ensure that your card is 100% compatible.
[edit] Running BOINC Client Software on Linux
The BOINC Client Software for Microsoft Windows® and Linux, is now available with a full GUI called the BOINC Manager or BBC Climate Change Program Manager.
[edit] Problems running BBC Climate Change Experiment
[edit] I cannot complete by the deadline / Are incomplete Work Units useful?
The simple answer is that the deadline is not enforced so work will be accepted after the deadline.
Note that Dave Frame (project co-ordinator) has said:
Even if people make it half way, we can use their results. Ideally, we want them to make it all the way to 2080, with their own personal planet Earth, but we do understand that that may not always be possible. But for us, the period 1960-2000 is really important because that's the period when we can test the model you're running against reliable, global data (data is much sparser before about 1960 - there's much more data once satellites began keeping an eye on those regions in which people don't live/ships and planes don't travel through). So please do continue if you can. The BBC are going to run a show in early summer, but as scientists we're interested in a much more comprehensive analysis after that, as well. After the BBC series finishes, we'll keep analysing the data for several years after this (and add new experiments and models, too).
[edit] Is my time to completion correct?
The Work Units are very large and do take months to complete. However the estimate of time to completion may be a little inaccurate. Taking the hours completed and dividing by proportion of work done may be more accurate. So if the task tab shows 94 hours to reach 4.07% of the way though the model then 94/.0407=2310 hours total time less 94 hours completed leaves 2216 hours to go. This could still be inaccurate as your model may get very slightly slower as it gets hotter but is likely to be more accurate than BOINC's to completion time.
Sometimes the time to completion displayed or the calculation above can be rather dubious due to rewinds. The calculation is finding you have run the model for a long time and have not got very far with the model. The calculation then comes out as very high (which is sensible given the information it is working on).
The model is designed to do some rewinds. If it hits a problem it should rewind a day. If it fails again it rewinds a month. If it fails again it rewinds a year but if it fails again it should give up.
If you have got less than a year into a model and it goes back to the beginning it could well be working as designed.
[edit] Why won't it do anything?
This question is a bit general and could be a few things:
- Have you attached to the project? If not see Getting Started.
- Is it struggling to communicate? If so, you may need to change your firewall see Firewall Configuration
- Has it been running but everthing seems to have stopped? Are you running BOINC version 4.45? If so, does this seem to happen with a failed benchmark giving the message Aborting CPU benchmarks, one or more active tasks are still running? If so, exiting BOINC and starting it again may get it going again. However, an upgrade to version 5 is recommended to prevent this recurring.
- Have you set the Preference "Do work while computer is in use?" to no? If so, the idle detection may be failing. Consider setting "Do work while computer is in use?" to yes. To do this go to 'Your Account' and then 'View or edit general preferences'.
[edit] If Models will not download due to lack of hard disk space, how do I fix it?
- Note that each model (Work Unit) requires 600MB of hard disk space. If you have a hyperthreaded processor this means 1.2GB of spare space is required for two virtual processors.
- Check your Disk Usage Preferences by going to 'Your Account' and select 'View or edit' General Preferences. Check all three Preferences (Use no more than (MB), Leave at least, and Use no more than (% of total space)) are compatible with providing at least 600MB per model.
- If all three Preferences are compatible with providing at least 600MB per model, then it could be your Resource Share. Your relative resource allocations control not only how much processing time each of them will get, they also control the percentage of the disk space available to BOINC that each project is allowed to use. This may prevent you from running BBC Climate Change Experiment if it is given a low resource allocation (because it uses lots more disk space than other BOINC Powered Projects). A potential solution here is to set the Resource Share for BBC Climate Change Experiment very high temporarily until you have downloaded your model.
- If a change is necessary, edit the Preferences and update on the web site. This will reach your computer on the next communication but to speed things up, update from BOINC to get the client to collect the new Preferences. It is now sensible to exit BOINC and restart it. Finally another update should then start the download.
[edit] Why is the text on the graphics display distorted?
A number of users with Matrox or S3 video cards and the latest drivers have reported garbled/unreadable text on the graphic Globe display.
However, a user with a Matrox card, reported turning bus mastering off in the display properties worked for him. See below:
I tried changing various resolution settings - no change, looked into the whole .txf thing, turned off Suitcase font manager just in case - no change and once i understood it relies on openGL / directx thing had a look at the adved settings options for the graphics card turned off dual head - no change turned off 32-bit Z-buffering - no change
Then I turned off bus mastering (right-click on the option and it explains this may cause DirectX problems with some programs) ...restarted... And it worked! Cool
So, in summary -
Display Properties > Settings > Advanced
Then Options tab > Performance > disable 'Use bus mastering' checkbox
hope this helps other matrox types - good luck :D Very Happy
[edit] Why is the show graphics button greyed out?
The button should be available when your model is running. If it is suspended, preempted or paused for benchmarks, it is normal for the button not to be available.
The button will also be greyed out if your model has crashed. If you haven't reached your daily quota (typically 1, 2 or 4 models) another model should download and start and the button should be usable again.
If you have crashed all models in your quota, then there won't be another model downloaded until the next day and the button will be greyed out. See next question.
[edit] What does Daily Quota reached mean?
Bad news, I fear. Your models are crashing. The quota is there to stop computers repeatedly downloading models and crashing them. To get around this you could reset the project.
Note 1. Do not reset the project if you have a model that is running, suspended, preempted or paused. 2. If all your models are crashing, it may be better to try to find the problem than just crash more models.
[edit] What does deferring communication mean?
This may be quite normal if there is information to upload but no connection is available. It may just be waiting until later to try again. However if there is an internet connection available it may be a symtom of a Daily Quota reached. See question above.
[edit] Performance issues
[edit] Timeslicing between BOINC projects & potential lost work
If you are time slicing make sure you've set your preferences to have Leave applications in memory while preempted? set to yes (the BOINC default is no). BBC Climate Change Experiment checkpoints every 432 Timesteps, and if you don't leave it in memory any calculations you've done since the previous checkpoint will have to be redone when BBC Climate Change Experiment starts up again. If other applications require the memory BBC Climate Change Experiment may get swapped out, but that's a much smaller overhead than you'd get if you were preempted at timestep 3 let alone timestep 431!
[edit] For more on performance see BOINC_FAQ: Performance
[edit] Questions, Problems and Discussion Forums
You can ask BOINC specific questions on the BBC Climate Change Experiment Questions Forum
We would like to encourage you to use the Climateprediction.net PHP forum where Participants can share their views, and perhaps provide advice on some of the common problems. Our team members and many knowledgeable Participants regularly read the posted messages, so most of your comments come to our attention within a few days if not hours or less.
Note: In order to post messages on the Climateprediction.net PHP forum, you will need to set up a forum account when you first activate your Account.
There is also a BOINC style BBC Climate Change Experiment BOINC forum.
If all else fails, go to the Contact & Support Centre to contact the climateprediction.net team. However asking questions on the boards usually works better. If it is serious issue a moderator will usually email someone from the Climateprediction.net Team.
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