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1) Message boards : Wieferich and Wall-Sun-Sun Prime Search : Which near-finds are shown? (Message 146496)
Posted 909 days ago by Profile Toshio Yamaguchi
I am not sure I understand which near-Wieferich and near-Wall-Sun-Sun primes are actually shown. In WW by the numbers it is stated "For numbers between 1e9 and the end of our PRPNet search, special instances with |A| <= 100 are shown". Doesn't this mean that, from the pages here and here, say 3411159925463651, to pick a random example, should be reported? Or is that sentence to be read "For numbers between 1e9 and the end of our PRPNet search, special instances with |A| <= 100 that were previously missed are shown"? If not, why are those primes not listed at the WW Statistics page? Or was that range part of the "very beginning of the current search (completed in the first day)" mentioned in the WW by the numbers thread? Thanks for any insight into this.
2) Message boards : Problems and Help : PRPNet "Connect to socket failed with error 101" with IPv6 (Message 139687)
Posted 1147 days ago by Profile Toshio Yamaguchi
where does the source code reside?

I think this is what you want.
3) Message boards : Project Staging Area : Chance of ESP Prime (Message 76910)
Posted 3290 days ago by Profile Toshio Yamaguchi
I don't immediately see a problem if the probabilities for the different k's are independent of each other and don't think the greater than 100% total percentage is an error in that respect. I interpret a value of over 200% as indicating that two primes can be expected in the 5-10M range.
4) Message boards : General discussion : Word Link #001 (Message 76665)
Posted 3301 days ago by Profile Toshio Yamaguchi
5) Message boards : Project Staging Area : 2014 PRPNet March Challenge (Message 76506)
Posted 3306 days ago by Profile Toshio Yamaguchi
Maybe continue the MEGA port until at least one prime has been found for each k and only refill those k without a prime when the port runs dry.
6) Message boards : General discussion : Word Link #001 (Message 76502)
Posted 3306 days ago by Profile Toshio Yamaguchi
7) Message boards : Project Staging Area : 2014 PRPNet May Challenge (Message 76486)
Posted 3306 days ago by Profile Toshio Yamaguchi
How do you get prpclient.ini to switch projects without causing workunits to be "abandoned" when resuming the original work after a few days?

Do you mean you want to receive work from, lets call it port 1 for simplicity, then pause crunching work from port 1, receive work from port 2, crunch that work to end and then resume the unfinished work from port 1?

If this is correct, then I don't think that is possible with the settings provided by PRPNet. What you could try is to manually move the checkpoint file for port 1 work out of the folder, switch to port 2 in prpclient.ini, crunch that work and return it and then comment out port 2 and uncomment port 1 again. Then move the checkpoint file back to the folder where it was and start prpclient again.

Please note that the above procedure comes without any warranty of correct functionality, I never tried that myself.
8) Message boards : Project Staging Area : 2014 PRPNet May Challenge (Message 76380)
Posted 3313 days ago by Profile Toshio Yamaguchi
Currently, none of my PRPNet directories contain a file named 'prpclient.ini'.
Is 2-dual-start-prpclient.bat supposed to create this file, or do I have to create it manually?

This should be created automatically either when running the install-prpclient script or the update-prpclient script, I am not sure which of them does it. start-prpclient only initializes the PRPNet client.
9) Message boards : General discussion : ~~~(,__,)^>'s New and Improved Thought for the Day (Message 76284)
Posted 3316 days ago by Profile Toshio Yamaguchi
At the summit is a man that, legend has it, knows how to stop Windows downloading updates.

Totally agree that Windows update can be a pain. I recently ran a large PARI/GP computation on my laptop and in the middle Windows began downloading updates. Fortunately I had the foresight to configure it to download but not automatically install the updates.

It's really not funny if you've run a huge computation for several days only to lose everything because of Windows rebooting the computer in the middle of the computation.
10) Message boards : Generalized Fermat Prime Search : Frequently asked questions (Message 75999)
Posted 3326 days ago by Profile Toshio Yamaguchi
Q.: What do I have to keep in mind when overclocking my GPU for the GFN project?
A.: There is no general answer that will apply to all users/systems/configurations, but here are some general guidelines:
1. As a rule of thumb, try to keep the card under 80°C. It has been observed that once the 80° range is exceeded, there might be stability issues.
2. If you are running on a laptop, don't overclock the GPU. It is generally not a good idea to run the most computationally intensive tasks on a laptop, anyway.
3. Go up in small increments when overclocking. For the most part, the shader and core clocks are linked for GFN work (the exception is for GTX 2xx cards and related Quadro/Tesla cards built on these chips). When you find a clock that is unstable, back off a couple of overclock steps and you should be fine (assuming #1 above isn't an issue).
4. If you are getting errors, lower the clocks on the GPU and consider running the GPU at stock clocks for GFN. (A maxErr exceeded error indicates an error related to overclocking).
5. The GFN project appears to be particularly sensitive to memory overclocks. These don't gain you greatly in overall speed increases anyway, so I wouldn't recommend playing with them at all. Indeed, if you are not overheating and haven't done much to the shader clocks but are still getting stability issues, you might consider downclocking the memory (similarly to the workaround for the GTX 550 Ti cards).
6. Remember that overclocking necessarily uses more power. This in turn puts more stress on your power supply, thereby increasing overall heat. This leads to several possible issues including A) over stressing the power supply resulting in shortened PS life span, possible shorts in other parts of your system such as the motherboard, and non-GPU instability; B) hotter running GPUs and CPUs (I have reduced heat in some systems just by installing a more powerful/efficient PS); and C) problems with GPUs that do not have extra power connectors (i.e., the PCIe slot is limited to 75W...overclocking some cards without external power can exceed this limit, and running at the limit can produce instability in some systems).
7. That GT530 you bought is never going to be a GTX 560 Ti (or fill in whatever card comparison you like). That is, you are not going to make a mid-range card out of an entry-level card nor are you going to make a top-end one starting with a mid-range. You may find that you can take a card from a particular series and overclock it successfully to perform at or near the stock clocked card from the next higher series (e.g., I have my wife's superclocked EVGA GTX 550 Ti performing about as well as a stock clocked GTX 460), but you are not going to be able to do better than that 99% of the time (*note: there may be rare exceptions). If you really want a top-end card, buy aren't going to overclock your way there with something else.

Q.: How do I tell the Boinc client to run GeneferCUDA on the correct GPU on a multiple GPU system?
A.: If you are running BOINC client 6.13.x or higher, you can use this construct in cc_config.xml to tell the client not to use a specific GPU for geneferCUDA:

<exclude_gpu> Don't use the given GPU for the given project. If <device_num> is not specified, exclude all GPUs of the given type. <type> is required if your computer has more than one type of GPU; otherwise it can be omitted. <app> specifies the short name of an application (i.e. the <name> element within the <app> element in client_state.xml). If specified, only tasks for that app are excluded. You may include multiple <exclude_gpu> elements. New in 6.13 <exclude_gpu> <url>project_URL</url> [<device_num>N</device_num>] [<type>nvidia|ati</type>] [<app>appname</app>] </exclude_gpu>

For example:

<cc_config> <log_flags> [...] </log_flags> <options> [...] <exclude_gpu> <url]</url> <device_num>1</device_num> <type>nvidia</type> <app>genefer</app> </exclude_gpu> <exclude_gpu> <url]</url> <device_num>1</device_num> <type>nvidia</type> <app>genefer_wr</app> </exclude_gpu> [...] </options> </cc_config>

Q.: Does a positive hit with Genefer prove that the tested number is prime?
A.: The test performed by Genefer is a PRP test, so a positive hit with Genefer doesn't prove that the tested number is prime, it only verifies it is a PRP. That means a deterministic primality test still has to be performed on the number to prove it prime. However, on the large GFN tasks, the chances of a pseudoprime reported as prime are quite low.

Q.: Why does my GPU task run with Genefer appear to slow down?
A.: The cause of this could be a screensaver, which forces the GPU to render screensaver graphics rather than crunching the task. Also make sure that the computer does not go to sleep when you don't use it.

Q.: How can I tell if my GPU is double precision?
A.: Every CUDA-enabled card has a "Compute Capability" (or CC) level. All cards with CC 1.3 or higher support double precision. The CC of a specific card is listed in the specifications for that card.

Q.: Why is my GFN WU progressing so slowly?
A.: GFN tasks run very slowly on some cards. For example, the 600-series Nvidia cards are really bad at double-precision arithmetic which genefer performs. The 600 are much better at doing single-precision arithmetic and such would me more suited for a project like PPS Sieve.

Q.: When using standard preferences (not app_info), how do I avoid getting GFN tasks for the CPU and only get GPU tasks instead?
A.: You can try the following:
1. On prefs page, uncheck "use nvidia gpu" and "use ATI GPU", and select only llr subprojects (the ones you want to run)
2. Open boinc and get a couple wu's. It may start to say "no selected work available". I so, do manual updates until you get what you want (it may take a few minutes)
3. After getting llr work, go back to prefs page, select GFN GPU and check the "use nvidia gpu" pane (leave only the "use ati gpu" unchecked).
4. Update boinc (you should get only gpu tasks this time).
After that, boinc only requests the selected work.

Q.: How can I prevent computation errors with GeneferCUDA?
A.: Please see this post.

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