This file lists the undocumented features available in the program.
These features may change or be discontinued at any time.  Their use is
totally unsupported.

In prime.txt you can force the program to use different filenames for 6 files.
You can also change the working directory (identical to the -W command line
argument).
	prime.ini=your_filename
	local.ini=your_filename
	worktodo.ini=your_filename
	prime.log=your_filename
	prime.spl=your_filename
	results.txt=your_filename
	WorkingDir=your_directory_name

Some options in prime.txt can be configured to have different values
at different times of the day using this syntax:
	Option=setting
where setting is defined as
	value OR value during list-of-times else setting
At present, only Memory, MaxHighMemWorkers, PauseWhileRunning, LowMemWhileRunning,
and PauseCheckInterval support this during/else syntax.  Also note you can
no longer edit these options from the user interface.  To use this feature,
you must manually edit the prime.txt/local.txt file.  An example in local.txt:
	Memory=500 during 1-5/17:30-24:00,1-5/0:00-8:30,6-7/0:00-24:00 else 200
The 1-5 and 6-7 refer to days of the week, with Monday=1 and Sunday=7.  The
time portion refers to the hours of the day based on a 24-hour clock.
You do not need to specify days of the week (e.g. 1-7/0:00-8:00
is the same as 0:00-8:00).  The above example lets the program use 500MB
during the week from 5:30PM to 8:30AM and all day on weekends.  Otherwise
(weekdays from 8:30AM to 5:30PM), the program can use only 200MB.

You can control whether the program does extra error checking on every
iteration of a primality test.  This runs a little bit slower.  Windows
user can control these options from the Advanced Menu.  Linux users must
add one or both of these lines to prime.txt to control these options:
	ErrorCheck=0 or 1
	SumInputsErrorCheck=0 or 1
The first line controls "ROUNDOFF > 0.4" error checks, the second line
controls "SUM(INPUTS) != SUM(OUTPUTS)" error checks.

You can control how the "count of errors during this test" message
is output with every screen update.  These messages only appear if
possible hardware errors occur during a test.  In prime.txt set:
	ErrorCountMessages=0, 1, 2, or 3
Value 0 means no messages, value 1 means a very short messages, value 2
means a longer message on a separate line, value 3 means a very long message
possibly on multiple lines.  Default value is 3.

You can force the Options/CPU dialog to display times using AM/PM or
a 24-hour clock format.  Otherwise, the program will make its best guess
as to the proper format.  Add this line to prime.txt:
	AMPM=n
where n is 1 for AM/PM formatting and n is 2 for 24-hour formatting.

You can adjust how many decimal digits of precision are displayed
in lines output to the screen.  In prime.txt enter a value between 0 and 6:
	PercentPrecision=n

You can choose whether the program uses the high resolution system clock, the
standard system clock, or the read timestamp counter instruction (RDTSC) to
time events.  By default the program uses the high resolution system clock if
available.  Choose one of these values for n (default is 1):
	0 - use the system clock.
	1 - use RDTSC but do not output clock counts.
	2 - use RDTSC and output clock counts.
The above values will only have an affect if a high resolution system clock
is not available.  You can force the program to bypass the high resolution clock
by adding 10 to one of the values above.  In prime.txt, enter
	RdtscTiming=n

You can alter the way the program outputs timings.  In prime.txt set:
	TimingOutput=n
Where n=1 for seconds with 3 digits of precision, n=2 for milliseconds
with 1 digit of precision, n=3 for milliseconds with 2 digits of precision,
n=4 for milliseconds with 3 digit of precision.

You can change the formatting of date and time to the screen.  In prime.txt:
	TimeStamp=n
where n=0 turns output off, n=1 is the default date/time without seconds,
n=2 is date/time with seconds, n=3 is time only without seconds, n=4 is
time-only with seconds.

You can have the timings that are output to the screen be cumulative
(from program restart or start of a new exponent) rather than resetting
after each screen output.  Add this line to prime.txt:
	CumulativeTiming=1

The program normally will not start any calculation until 90 seconds after
a reboot.  This is done so that your normal boot up procedure can be as
fast as possible.  You can control how long this delay is by adding this
line to prime.txt, where n is the number of seconds to sleep:
	BootDelay=n

Some machines report much better timings if the worker threads stagger
their starts.  This was first noticed on Core i7 machines running Windows.
Presumably staggering starts improves timings due to each worker allocating
contiguous memory.  You can control how long the program waits between
starting each worker.  In prime.txt, enter:
	StaggerStarts=n
where n is the number of seconds to wait.  The default is 5 seconds.

The program supports 4 different code paths for LL testing depending on
the CPU type.  It also has a few different factoring code paths.  You can
force the program to choose a specific code path by setting the proper
combination of these settings in local.txt:
	CpuSupportsRDTSC=0 or 1
	CpuSupportsCMOV=0 or 1
	CpuSupportsPrefetch=0 or 1
	CpuSupportsSSE=0 or 1
	CpuSupportsSSE2=0 or 1
	CpuSupports3DNow=0 or 1
This shouldn't be necessary though as the program uses the CPUID instruction
to see if the CPU supports these features.

The program also supports different code paths for LL testing on a Pentium 4
based on the size of the L2 cache.  You can explicitly specify the L2 cache
size although this shouldn't be necessary since the program uses the CPUID
instruction to determine the L2 cache size.  In local.txt enter:
	CpuL2CacheSize=128 or 256 or 512
	CpuL2CacheLineSize=32 or 64 or 128
	CpuL2SetAssociative=4 or 8

The program automatically computes the number of CPUs, hyperthreading, and speed.
This information is used to calculate how much work to get.
If the program did not correctly figure out your CPU information,
you can override the info in local.txt:
	NumCPUs=n
	CpuNumHyperthreads=1 or 2
	CpuSpeed=s
Where n is the number of physical CPUs or cores, not logical CPUs created by
hyperthreading. Choose 1 for non-hyperthreaded and 2 for hyperthreaded. Finally,
s is the speed in MHz.

As an alternative to the above, one can set NumPhysicalCores=n in local.txt.
This is useful on machines that are somtimes booted with hyperthreading enabled
and sometimes without.  Normally, the program can detect this situation, but one
notable problem case is a dual-CPU hyperthreaded machine,  For example, take a
dual-CPU quad-core hyperthreaded machine.  When booted with hyperthreading enabled
this is properly detected as an 8-core hyperthreaded machine.  When booted
with hyperthreading disabled, this is improperly detected as a 4-core hyperthreaded
machine.  If you set NumPhysicalCores=8, then the program will set the 
hyperthreading state properly no matter how the machine is booted.

The program used to do factoring and P-1 testing on exponents even if
they were not the first entry in worktodo.txt.  The rationale was that
if the number had a factor, the server could be contacted and another
exponent reserved.  This avoids the possible scenario where the LL test
for the first worktodo.txt line completes, a factor is quickly found for
the second line in worktodo.txt and the computer now sits idle until
the server can be contacted.  This behavior was confusing, especially
to newcomers.  To restore this old behavior add this line to prime.txt:
	SequentialWorkToDo=0
One added benefit is time estimates in Test/Status will be more accurate
because we'll know no factors will be found and the LL test must be run.

The program will restrict how many exponents can be added to worktodo.txt.
To override this, change prime.txt:
	MaxExponents=n

By default, ECM will stop when a new factor is found.
You can have ECM always stop or always continue searching for factors by
using a value of zero or one in prime.txt:
	ContinueECM=n

You can skip the GCD in stage 1 of P-1 factoring with this prime.txt setting:
	Stage1GCD=0

You can have the program generate save files every n iterations.  The files
will have a .XXX extension where XXX equals the current iteration divided
by n.  In prime.txt enter:
	InterimFiles=n

You can have the program output residues every n iterations.  The default
value is the InterimFiles value.  In prime.txt enter:
	InterimResidues=n

By default P-1 work does not delete the save files when the work unit completes.
This lets you run P-1 to a higher bound at a later date.  You can force
the program to delete save files by adding this line to prime.txt:
	KeepPminus1SaveFiles=0

You can force the program to skip the trial factoring step prior to
running a Lucas-Lehmer test.  In prime.txt add this line:
	SkipTrialFactoring=1

You can do "optimal" P-1 factoring of k*b^n+c by adding lines to worktodo.txt:
	Pfactor=k,b,n,c,how_far_factored,num_primality_tests_saved
For example, Pfactor=1,2,10000157,-1,64,2.0

You can reduce the number of times worktodo.txt is read and written by
setting in prime.txt:
	WellBehavedWork=1
This only works for worktodo.txt files that contain only Factor= lines.
Only turn this on if you have BIG worktodo.txt files and each Factor=
operation does not take much time.  You must stop the program before manually
editing the worktodo.txt file.

In Advanced/Time, you can enter a value between 9994 and 9999 for the
exponent to run a QA script.  The QA file looks like this:
	64511,0,400,99999999,3389BC878321980A
Where the first value is the exponent, the second value is the FFT size where
zero means use the default FFT size.  The third value is the number of
iterations to run.  The fourth value is the shift count (if the shift count
is greater than the exponent a random shift count is used).  The final value
is the expected 64-bit residue.
The dialog box values between 9994 and 9999 force slightly different
code to run.  9999 and 9998 run straightforward squaring code, 9998 differs
by gathering some standard deviation data.  9997 does squarings also
but exercises the general purpose add/sub/mul routines too.  9996 does
operations typical during ECM - the final residue won't match but the
convolution error data can be useful.  9994 and 9995 probably blow up.

Advanced/Time of exponent 9990 forces reading of a file called
factors.  The program then tries to refind each factor using the
factoring code.  This is not an efficient way to verify factors as it
goes through the entire sieving process and trial factoring many
potential factors. 

You can control which FFT sizes are tested by the torture test.  In prime.txt
you can set:
	MinTortureFFT=n
	MaxTortureFFT=m
Where n and m are in "K".  The default for n and m is 8 and 1024 which will
run tests on FFT sizes rom 8K to 1024K.  Set n to 8 and m to 16 and you will
run only small FFT sizes.  These FFTs will fit in the L2 cache and may be
more stressful to the CPU.

You can control how many minutes each FFT size is tested by the torture test.
In prime.txt set:
	TortureTime=n
The default value is 15 minutes.

You can control how much memory the torture test uses.  In prime.txt set:
	TortureMem=n
The default value is the larger of your daytime and nighttime memory settings.
If this is set to 8MB or less, then the torture test does FFTs in-place.  This
may be more stressful but could miss memory errors that only occur at a
specific physical address.

The program normally does round-off error checking every 128 iterations.
When you are testing an exponent near the limit of an FFT length, the program
does this error checking every iteration.  
	NearFFTLimitPct=value
The default value is 0.5 (if the exponent you are testing is within 0.5% of the
maximum exponent that can be tested using the current FFT length, then the
extra error checking is performed).  A value of 0.0 will turn off this extra
error checking.

WINDOWS ONLY:  When Tray Icon or No Icon is selected the "X" at the right of
the title bar will minimize rather than exit.  You can make the program exit
if you prefer.  In prime.txt set:
	ExitOnX=1

WINDOWS  ONLY: You can change the Windows NT/2000/XP service name and service
display name.  The default for both is "Prime95 Service".  In local.txt, set:
	ServiceName=your service name
	DisplayName=your service display name
You may need to turn off the "Start at Bootup" and exit, change the local.txt
file, restart prime95 and turn the "Start at Bootup" option on to make this
change effective.

The program no longer uses hard FFT crossover points.  The soft crossovers
have two adjustments in prime.txt:
	SoftCrossovers=n
	SoftCrossoverAdjust=n
The first setting controls which exponents are examined.  The default value
is 0.2.  This means that an exponent that is 0.2% above or below an FFT
crossover point are tested for the best FFT size to use.  A value of 0.0
will turn off this soft FFT crossovers feature.  The second setting
defaults to 0.000.  This controls how aggressive or conservative the program
is in selecting the best FFT size.  The program normally uses the smaller
FFT size if the average roundoff error is below a value in 0.241 to 0.243
range.  If you set SoftCrossoverAdjust to say 0.003 then the program will
use the smaller FFT size if the average roundoff error is below a value
in 0.244 to 0.246 range.  This will generate more iterations that generate
roundoff error above 0.40 warnings and a time loss returning to the previous
save file.  It also increases the chance that a deadly roundoff error
above 0.6 will occur.  On the plus side, using the smaller FFT size each
iteration will be a bit quicker.  I wouldn't set this adjustment to more
than 0.006. If you set SoftCrossoverAdjust to say -0.002, then the program
will be more conservative and use the larger FFT size more often.

Alexander Kruppa wrote some code that allows the output of ECM stage 1 to
be passed to Paul Zimmermann's more efficient GMP-ECM stage 2.  This program
is usually faster in stage 1.  You can activate this feature by entering
	GmpEcmHook=1
in prime.txt.  Then select ECM bound #2 between 1 and bound #1.  Results.txt
will contain data that can be fed to GMP-ECM for stage 2.

In rare cases, users have reported the program can interfere with the
performance of some programs such as disk defragmenters and some games.
You can pause the program automatically when these programs are running by
adding this line to prime.txt:
	PauseWhileRunning=prog1[n1],prog2[n2],etc
The [n1], [n2] values are optional and indicate the number of worker threads
to pause when prog1 and prog2 are running.  The default value for n1 and n2
is to pause all worker threads.  Note that the program will pause if the program
name matches any part of the running program's file name.  That is "foobar"
will match "c:\foobar.exe", "C:\FOOBAR\name.exe", and even "C:\myfoobarprog.exe".
Also, if prog1 is "*" the program will pause no matter what.  Examples:
	PauseWhileRunning=*[1] during 6-7/2:00-3:00
	PauseWhileRunning=* during 23:00-24:00 else decomp[1],mygame[2]
The first example pauses one worker thread on Saturday and Sunday between
2AM and 3AM.  The second example pauses all workers between 11PM and 12AM and
pauses 1 worker if decomp is running and 2 if mygame is running.

LowMemWhileRunning is similar to PauseWhileRunning.  This option does not
allow workers to use a lot of memory.  This example in prime.txt will make
sure the program is using the minimum amount of memory possible while
photoshop is running:
	LowMemWhileRunning=Photoshop

By default, the program will check the PauseWhileRunning list every 10 seconds.
You can adjust the time period with this prime.txt setting:
	PauseCheckInterval=n
where n is the number of seconds between checking which programs are running.

LINUX/FREEBSD/APPLE ONLY: In prime.txt you can have mprime suspend one worker
when the system load gets above a threshold.  This can improve system responsiveness
by freeing up memory that mprime is currently using.  Mprime bases
its decisions using the first average displayed by uptime.  In prime.txt, set
	MaxLoad=a
	MinLoad=b
	PauseTime=c
For example, if MaxLoad is set to 4.5, mprime will suspend a worker whenever the
load average gets above 4.5.  If MinLoad is set to 3.1, then mprime will
resume one worker when the load average goes below this value.  Set PauseTime
to how often you want the program to check the load average.  This value
is in seconds.

Normally, the program will unreserve an exponent if it is scheduled to start
thirty days after the Test/Primenet Days of work to get value.  You can adjust
this interval by setting in prime.txt:
	UnreserveDays=n
where n is the number of days.  You should increase this value if you are
loading up worktodo.txt with a large amount of work and do not want any of
the work to be unreserved.

WINDOWS ONLY:  By default, Prime95 uses RAS routines to determine if your modem
is connected to the Internet.  Microsoft now prefers the InternetGetConnectedState
call in WININET.DLL.  To use this method instead of the RAS routines, add this
line to prime.txt:
	AlternateModemDetection=1

LINUX ONLY: Mprime supports 4 different ways of checking if your computer
is connected to the internet.  Set RouteRequired=n in [PrimeNet] section
of prime.txt.  The following values of n are supported.  The last entry is
what happens if RouteRequired is not given.
	0:	Assume computer is always connected
	1:	Assume connected if there is an entry in /proc/net/route
		other than for the loopback device.
	2:	Assume connected if there is an entry in /proc/net/route
		with a netmask of 00000000.
	none:	Same as 2 except that if /proc/net/route is unreadable
		mprime assumes computer is connected.

If you are running on a laptop or in a hot room and you want to slow the
program down to reduce heat, then you can add this line to prime.txt:
	Throttle=n
where n is the percentage of time the program should run.  For example,
Throttle=40 means the program will run 40% and be idle 60% of the time.

NOT IMPLEMENTED:  To limit the program's impact on computer responsiveness on a
hyperthreaded machine the program pauses for 30 seconds if two successive iterations
take 40% longer than a typical iteration.  You can turn this feature off or change
how long the program pauses by adding this line to prime.txt:
	HyperthreadingBackoff=n
where n is zero to turn the feature off or n is the number of seconds to pause
after two successive slow iterations.

Since P-1 stage 2 runs faster with more memory available you can have the
program only run stage 2 at night when more memory is available.  In
prime.txt set:
	OnlyRunStage2WithMaxMemory=1

You can control the maximum prime.log file size.  The default is 2MB.  Add
this line to prime.txt to change the default:
	MaxLogFileSize=n

You can use the old sockets communication code instead of the robust CURL library.
Add this line to the [PrimeNet] section of prime.txt:
	UseCURL=0

When not using CURL , you can control what type of URLs are used to contact the
PrimeNet server.  In the [Primenet] section of prime.txt enter:
	UseFullURL=n
where n is 0 for use relative URLs, 1 for use full URLs, 2 for try full URL
and if an error is returned try a relative URL.  The default setting is 2.
Note that a full URL is always sent when using a proxy server.

When not using CURL and using a proxy server, the program sends the port number
in http strings.  That is the ":80" in "http://mersenne.org:80/cgibin_text".
At least one proxy server only works if the ":80" is not present.  In this case, set
	SendPortNumber=0
in the [Primenet] section of prime.txt file.

When not using CURL, you can add additional information to the HTTP request
sent to the server.  This might be useful in some tough firewall setups.
In the [Primenet] section of prime.txt enter:
	OtherGetInfo=string
where string is any text up to 256 bytes.

The benchmarking code by default only times a subset of the large FFT sizes.
In prime.txt, set
	MinBenchFFT=n
	MaxBenchFFT=n
	OnlyBench5678=0 or 1
	BenchAllComplex=0 or 1 or 2
	AllBench=0 or 1
to alter these defaults.  The first to specify the range of FFT length (in K).
Enter an n value between 1 and 32768.  Set OnlyBench5678=0 to time FFT
lengths other than 5*2^n, 6*2^n, 7*2^n, and 8*2^n.  Set BenchAllComplex to 0 for
timing real FFTs only, 1 for real and complex FFTs, 2 for complex FFTs only.
Set AllBench=1 to time FFT implementations optimized for other L2 cache sizes 
and CPU architectures.  This is only useful during the development cycle to find
the optimal FFT implementations for each CPU.

If you want to run the program on several machines this is typically done
by carrying the program and files around on portable media such as a floppy
or USB memory stick.  In this case, you need to defeat the program's
automatic detection of hardware changes.  To do this, in prime.txt set
	FixedHardwareUID=1

Adding 32 to the MergeWindows value in prime.txt suppresses screen output
of the "Comm thread", "Main thread", "Work thread" prefix.

The Memory=n setting in local.txt refers to the total amount of memory the
program can use.  You can also put this in the [Worker #n] section to place
a maximum amount of memory that one particular worker can use.

You can set MaxHighMemWorkers=n in local.txt.  This tells the program how
wany workers are allowed to use lots of memory.  This occurs doing stage 2
of P-1 or ECM on medium-to-large numbers.  Default is available memory / 200MB.

The program makes its best guess at how the OS maps hyperthreaded logical CPU
numbers to physical CPUs.  It also assigns workers and helper threads
to CPUs for optimal speed.  However, bugs, new architectures, or situations we
haven't considered may make different affinity settings desirable.  In
local.txt set
	AffinityScramble2=string
Where the characters in "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz()"
represent 64 logical CPU numbers.  For example, let's say you have a system
with 8 logical cores with 4 workers each using a helper thread.  Also, assume
your system has logical CPUs 0 & 4 on the same physical CPU core, 1 & 5, etc.
If the program is properly determining which logical CPUs share the same physical
CPU, then the program internally generates an affinity scramble string of "04152637".
The program's default policy is to assign the worker and helper threads to the same
physical CPU.  If the program is not properly determining which logical CPUs share the
same physical CPU, or you think a different affinity policy would result in better
performance, then set AffinityScramble2 accordingly.  Let's say you think
running the helper threads on a different physical core would be better, then
you might set AffinityScramble2=02134657 to test out your theory.

In the prime.txt file, the DaysBetweenCheckin value can be set to any value
between 0.04 and 7.0.  Some SeventeenOrBust users want to send updates hourly.

In local.txt, add the line
	UseLargePages=1
to attempt using 2MB pages under Windows Vista.  Warning: these pages will
never be swapped out.  Thus, using this option could negatively impact
the performance of other applications.  Also, you'll need to have
the "Lock Pages in Memory" privilege to use this option.

LINUX/FREEBSD/APPLE ONLY: In prime.txt you can have set the nice level.  By
default, on startup mprime automatically sets the program to nice priority.
This isn't really necessary since worker threads are usually set to at a much
lower priority.  However, sysadmins might be alarmed to see a CPU intensive
program not running at nice priority when they execute a ps command (it takes
a more complicated ps command to see that the CPU intensive threads are running
at a lower priority). You can change the nice level in prime.txt with the line:
	Nice=n
where n is the nice level. The default nice level is 10.  In linux you can select
a value from -20 to +19.  In FreeBSD and Mac OS X you can select a value
between -20 and 20.  Higher numbers represent a "nicer" program (lower priority).
In all OSes, a zero nice level means run at the normal priority.

