Welcome...: How GIMPS Works

# HOW GIMPS WORKS

- This program is used to find Mersenne Prime numbers. Mersenne numbers can be proved composite (not prime) by either finding a factor or by running a Lucas-Lehmer primality test.
- GIMPS requires a Pentium class computer that is on most of the time. The program runs at the lowest possible priority. You should not see any impact on your system's performance. The program will use about 8MB of memory and about 10MB of disk space.
- Most importantly, you will need a lot of patience. Roughly speaking it will take about a month to run a single primality test - visit the benchmark page for a more accurate estimate on your computer.
- The program talks to PrimeNet, a central server on the Internet, to get work to do and report results. The program communicates using the HTTP protocol and may require a little extra configuration to get through some firewalls. The program only sends a few hundred bytes every week or two. Thus, there is no impact on your network performance. The program does not require a continuous Internet connection and if properly configured will not automatically dial out to establish an Internet connection.
- There are three types of work assigned by the server. PIII-900 and faster computers get first-time primality tests. These tests require the most work and have the best chance of finding a new Mersenne prime. Pentium-233 and faster computers get double-check assignments. These assignments do not take as long and can find a Mersenne prime only if the original test had a problem. The slowest computers are assigned factoring work. This helps by eliminating some exponents for the faster computers.
- Every half hour the program saves its state so that if there is a computer crash you will lose at most a half-hour of work. All temporary files and program settings are conveniently stored in the same folder as the program.
- Before you complete your assignment, the program will get more work to do. This will assure that your computer has a continuous supply of work.
- If you are lucky enough to find a new Mersenne prime, the program optionally notifies the server and optionally emits a continuous sound to notify you of the happy news!