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  1. We have added one word to the End User License Agreement (EULA), but it is an important word.  The EULA can be found at

     

    http://folding.stanford.edu/English/License

     

    We added the word "written" to this sentence:

    "You may use this software on a computer system only if you own the system or have the written permission of the owner."

     

    We felt that this was an important addition in order to avoid any confusion.  There have been a few situations where donors felt that they had permission, but the owners of the computers did not.  Having written permission is the best way to make sure that there is no doubt.  It also gives protection to the donor in that he/she would then have proof of permission, avoiding problems involving oral agreements.

     

     

    Voir l'article complet


  2. We have another paper that came out recently (paper #60 at http://folding.stanford.edu/English/Papers).  This one describes the PS3 client in FAH:

     

    by Edgar Luttmann, Daniel L. Ensign, Vishal Vaidyanathan, Mike Houston, Noam Rimon, Jeppe Øland, Guha Jayachandran, Mark Friedrichs, Vijay S. Pande. 

     

    'In this paper, we detail how we were able to get great speed increases for Folding@home (and actually certain molecular dynamics calculations in general) on the PS3. This is our first paper using the PS3, laying out the "how does it work," with a follow up paper in the works describing the results obtained in FAH from PS3 clients. 

    It is also worth noting that this paper is a collaboration between FAH team members (Luttmann, Ensign, Vaidyanathan, Houston [now at AMD], Jayachandran, Friedrichs, and Pande) with developers at Sony (Rimon and Øland and their coworkers). 

     

    Here's the more technical abstract as well:

    Implementation of molecular dynamics (MD) calculations on novel architectures will vastly increase its power to calculate the physical properties of complex systems. Herein, we detail algorithmic advances developed to accelerate MD simulations on the Cell processor, a commodity processor found in PlayStation 3 (PS3). In particular, we discuss issues regarding memory access versus computation and the types of calculations which are best suited for streaming processors such as the Cell, focusing on implicit solvation models. We conclude with a comparison of improved performance on the PS3's Cell processor over more traditional processors.

     

     

    Voir l'article complet


  3. We have another paper (paper #59 at http://folding.stanford.edu/English/Papers)

     

    by Paula M. Petrone, Christopher D. Snow, Del Lucent, and Vijay S. Pande.  Proceedings of the National Academy of Sciences, USA
    2008

     

    which recently was published, representing a major step for FAH. 

     

    This one deals with the ribosome. The ribosome is a fascinating molecular machine, responsible for the synthesis of proteins. For this reason it is of fundamental importance to protein folding (as the last step in the central dogma of biology) as well as to human health (since the ribosome is the target of a very large fraction of antibiotics). One of the questions revolving around ribosome function is why is there a large tunnel inside the ribosome, through which proteins exit after being synthesized. In this paper, we used "bigWU" classic clients (clients which allow larger systems to run) since the ribosome is so huge that it would not run on regular classic clients.

     

     The primary goal of this paper was to analyze the surface of the ribosome tunnel. Understanding the nature of this surface would be useful for both understanding the fundamental nature of protein synthesis as well as how key antibiotics interact with the ribosome. An interesting related discovery was the identification of a potential "ribosome gate" which can open and close selectively, based on what is interacting with the gate. This suggests novel hypotheses for several aspects of ribosome function as well as interesting new directions for work on studying the ribosome and for new routes for antibiotics.

     

     

     

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  4. I am very happy to announce that a first key work (paper #58 at http://folding.stanford.edu/English/Papers) from the Folding@home project on Alzheimer's Disease (AD) was just published

     

    Simulating oligomerization at experimental concentrations and long timescales: A Markov state model approach, by Nicholas W. Kelley, V. Vishal, Grant A. Krafft, and Vijay S. Pande.   J. Chem. Phys. 129, 214707 (2008); DOI:10.1063/1.3010881 

     

    url:  http://link.aip.org/link/?JCP/129/214707

     

    Abeta misfolding and aggregation is believed to be the cause of Alzheimer's Disease. Simulations, like Folding@home, are a natural way to understand this process. However, there are several key challenges for simulating the key step -- oligomerization.

    This work represents a new way to simulate Abeta oligomerization, with a key advance of being able to simulate experimentally relevant timescales and concentrations, using a novel method. We use this new method and the power provided by Folding@home donors to simulate oligomerization in all-atom detail. This has lead to specific predictions about the process, which we are now testing experimentally. 

    In many ways, this paper is the "tip of the iceberg" for the Folding@home activities in AD, with a lot more interesting results to come, especially in terms of experimental tests of our predictions and interesting new possibilities for new drugs and AD therapeutics.  So, while we're excited that this result is now past peer review, we're even more excited for what's coming down the pipeline, waiting peer review.  We'll keep you posted as more results become public, hopefully with some even bigger announcements in 2009.

    UPDATE:It was asked which clients participated. This work started several years ago and took some time to analyze and then publish. So, it ran exclusively on classic clients. For the follow up simulations, we are using a mixture of GPU, SMP, and classic clients. Due to the large number of classic clients, they allow us to calculations not possible on the other platforms. However, the raw speed (but smaller number) of the GPU and SMP clients allow us to get a good rough idea quickly, refining later with classic clients.

     

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  5. It's been a while since I've posted on this topic, so I thought it would be a good time to talk about the long term vision for FAH.  In the first few years, we have done a lot to build up methodology (novel distributed computing algorithms, tests of methods), especially in the last years working to bring GPU's, PS3's, and tightly coupled SMP calculations to a distributed computing platform.  While all of this has been going on, there has been a lot of work which would have a direct impact to disease and human health, and donors should see more results (i.e. papers) coming out in this direction soon.  In particular, results on Alzheimer's Disease, Huntington's Disease, and some other surprises in the works (sorry, some details are best left until peer review is done).

     

     

    In terms of a long term vision for the FAH software, our short term goals is to shore up the SMP client.  Just as there was a big improvement from the GPU1 -> GPU2 client, we have been working steadily on an SMP2 client -- a version which is much easier to use, requires less donor effort, and scales much better.  This really is a combination of a modified client and (especially) new cores.  This effort has been going on for about a year and it's far enough along that I'm starting to talk about it publicly.

    In the previous post, I also mentioned about some of our work behind the scenes in revamping the backened of FAH, i.e. a whole new set of server codes.  We have code for the workserver and collection servers, but in time we expect the full backend to be cleanly rewritten from scratch.

    Longer term, with a more solid GPU2 and SMP2 clients done, we can then move on to other areas.  Our goal is to be bleeding edge in the nature of our science, but get back to the simplicity and stability found in the classic client.  We still have a ways to go, but I am excited that projects that were started some time ago are now looking like they will see the light of day.

     

    Voir l'article complet


  6. We've made some changes to the Collection Servers (CS) which seems to be making a big difference.  We've migrated them to a new network (the old net had many issues, as discussed in previous posts) and recently made some configuration tweaks.  The two new CS's (171.67.108.17 and 171.67.108.25) seem to be doing reasonably well right now.

     

     

    Hopefully, this will help donors get WUs in faster and allow the FAH team some leeway when a server goes down, knowing the CS is there as a backup.  We'll continue to monitor the CS issue, since this is such a critical part of FAH.

     

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  7. Engineers at NVIDIA (notably Scott LeGrand) have come up with a theory for the EUE's seen in core 1.15 (and a few others in the 1.15 to 1.18 range) on certain hardware. They found that this core had code optimizations that drove the GPU so hard that it would draw a lot more electricity (one sign of this was running hotter). In some boxes, this was too much electricity and this lead to numerical instabilities. When the same machine was given a beefier power supply, the problem went away.

     

    We've been told that 8800's require 600W power supplies, but we're finding that even a little bigger (eg at least 650W) is important to leave some room for error. We are working to see if there is some way to detect this issue in software, but for now, if you're getting EUE's on the NV GPU client, this is something to consider.

     

    By the way, this will be very important for us to consider future code optimizations. NV core v1.19 removed some optimizations to solve this problem, but there are many cards which would run fine w/this more optimized code. If we can find a way to detect whether the card can draw enough power, we may be able to choose different code paths to allow for greater optimization for cards which can handle it.

     

    We're still looking into this. For now, if you're seeing issues with your card, please consider trying out a bigger power supply. We will continue to look to see if this is indeed the problem and what we can do to help the situation such that the code runs stably on all machines.

     

    PS Please post replies here:http://foldingforum.org/viewtopic.php?f=52&t=6755

     

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  8. We're happy to announce that the PS3 client for Folding@home has won a prestigious design award:

     

     

    The PS3's Folding@home service has nabbed a prestigious Good Design Award, AKA "G-Mark." Since 1957, the Good Design Award has been instituted by the Japanese Ministry of International Trade and Industry to award outstanding design in industrial and consumer products.

     

    Here are some more links.  First a news site discussing it

    http://kotaku.com/5078119/foldinghome-wins...se-design-award

     

     

     

     

     

    and the Sony Press Release

     

     

    http://www.scei.co.jp/corporate/release/081106de.html

     

     

     

    Voir l'article complet


  9. The Stanford CS building was off line briefly today starting at about 1:30pm pacific time, lasting for about 3 hours.  This meant that all of our machines on the 171.64.65.xx subnet were off line.  It looks like everything is back on line and Stanford IT is looking into causes.  This will likely lead to a bit of an excess load for a while until things settle down.

     

     

     

    Voir l'article complet


  10. We will have a brief (1 hour) server outage tomorrow, October 28 at 10am pacific time.  It is expected to last about an hour.  This will only affect machines on the 171.64.65.XX network, so most of FAH will be up.  However, we expect there to be a server backlog for a little bit after the machines come back up.  Also, it's likely that one server or so will have trouble coming back up and will be delayed.

     

     

     

     

    Voir l'article complet


  11. As I've discussed before, we have been having issues with a particular subnet (171.64.122.XX) for Folding@home servers.  The symptoms were dropped connections and general challenges returning WUs.  We asked for a new network, just for Folding@home, and after much red tape we have received it and it has been installed on a few trial servers.  So far, it is looking very promising.  VSP07v (171.67.108.11) is an example of a server interface on the new network and it is behaving very well.  We are in the process of updating additional servers.  It's still possible that this isn't a network issue, but given our results with VSP07v, that looks unlikely, so we hope we can now see the light at the end of the tunnel.

     

     

    We have also started rolling out new GPU servers.  The GPU serverstat pagehttp://fah-web.stanford.edu/localinfo/contact.GPU.html

    now shows more servers in general, as well as a much lighter load.  This was possible now that we have the new network.  If all looks good, we'll plan on rolling more out in time.

     

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  12. There have been two issues which have been causing FAH some series issues. I wanted to give an update.

     

    First, networking on subnet 171.64.122.XX seems to be very slow and easily overloaded. Our diagnostics (and donor input) points to this issue being caused by a firewall on this subnet that can't handle the load. I have asked 3 different branches of our IT dept looking into this, but nobody has any fixes just yet. Getting impatient with this slow response, some time ago I requested for us to get a new network for our machines. This request is being processed. Once it's accepted, it will take a little time for them to get the new net in there (they may be able to do a VLAN, but more likely they will have to run a new physical cable, since the VLAN would still be behind the firewall). This subnet also has some of our collection servers, so this will be a big help there too once this is resolved.

    Second, the current server code can get overloaded. When it does, it slows down. However, new code in the server notices this and restarts the server binary. This leads to downtime of about an hour when this happens. While, this does autofix the problem with just a little downtime, I'd like zero downtime (as would most people). I have paid a professional software house to rewrite our FAH server backend from scratch. That is almost done (it's in QA right now, with some somewhat minor issues to address). This new server code should address this issue (and other issues) with the server code, but may introduce new issues that need to be smoothed over. However, the rewrite is MUCH cleaner architected and so that will be important going forward in the future.

    I just wanted to give a bump to let people know where we are. These issues aren't quick to resolve, but we are making progress. The new server code in particular will be a big help in the next 5 years of FAH, due to its rearchitecting and much cleaner code.

     

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  13. We've been looking into the issues some people have been finding with the viewer. On the ATI/AMD side, the catalyst 8.9 drivers seem to have resolved a number of issues with the viewer.

     

    On the NVIDIA side, we have also now released on our download page a special version of the viewer designed for NVIDIA GPU's; this viewer has modifications that makes the viewer run much more smoothly and in general and behave better on a broader range of NVIDIA GPU's. If you're curious to run the viewer, please check it out (on our high performance client download page).

     

     

     

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  14. In partnership with Sony, we've rolled out a new update to the Folding@home client for the PS3, now built into their "Life With Playstation" (LWP) application. They've done a great job of building a beautiful piece of software. Folding@home is running underneath in the background. Noam Rimon, the lead developer on the Sony side put it well in an earlier blog post as well as a more recent post on the PS3 blog

     

    We’re going to offer this as a free service that will be easily accessible directly from the XMB. Life with PlayStation will feed live content to your PS3 with updates on news and weather on a visually stunning and interactive global map. Imagine being able to wake up to your PS3 to see if you need to pack an umbrella for the day. Or just relax as you listen to your favorite tunes while reading up on top news from around the world.

     

    We've also updated the science code to do the same functionality of what the GPU2 code can do today. However, people will notice that the ns/day will go significantly down. We want to stress that the points per day remains the same. This means that one gets more points/ns since the calculation is more complex, so don't worry too much if your ns/day is lower. LWP takes up a little extra compute time from the science, but not much. Most of the decrease in ns/day is due to the fact that it's doing a much more complex calculation (which is good for the science side of this).

    There's also a nice Video demo done by Noam Rimon showing the functionality of LWP:

     

     

     

     

    We'll give further updates about this as time goes on, but we're excited to have the new science functionality in and to have a client which hopefully can even further broaden the participation of PS3 owners in Folding@home.

    PS Some people have noticed that LWP seems slower. In particular, the ns/day count is down, but that's not what it might seem. We're doing more complex science which runs slower on the PS3, so that's responsible for most of the slow down you're seeing.

    For those who are interested, it's slower because we're running a more complex version of the GB implicit solvent, which is much more computationally demanding; the upside is that this would be much more accurate. This is also the main solvent model we're running on GPU2 right now. In fact, earlier PS3 results pointed us to the significance and importance of moving to this new model, so this (and GPU2) reflects what we've learned so far.

     

    However, there is a small performance hit due to all the other life with Playstation (LWP) eye candy. However, it's not very big in the end (the Cell and RSX GPU are very powerful), with most of the slow down in terms of ns/day coming from the new science code. The upshot of the LWP platform will hopefully be getting a lot more PS3 donors (but I guess time will tell there).

     

    So far, the response will be strong and I expect that this could in time double the FLOP count from PS3 donors in Folding@home, which itself will be pretty impressive. More importantly, with the advanced science now rolled out on both the PS3 and GPU2 platforms, we're well-poised to tackle some much more complex and interesting calculations.

     

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