On 18 Apr 00, at 0:34, Siegmar Szlavik wrote:
> I don't say that prime95/ntprime has a problem, just that it can
> make (serious) problems on some systems and they don't go away until
> it gets uninstalled. I don't think it has to do with a memory leak,
> because if it comes to the point where the system is no longer
> useable (for example it takes 20-30 seconds to start a program like
> the NT explorer) in the majority of the cases the system is already
> not useable directly after reboot.
Ah, this _is_ a bit different.
I take it you're running Win NT WS 4.0 SP 4+ (as I said before, you
really _should_ be running SP 6a, but anything previous to SP 4 is
definitely going to leave you open to numerous problems).
Did you try disabling NTPrime (Control Panel/Services/Startup) so
that it doesn't start automatically at boot time? Does this cure the
problem? Does the problem reappear if you then manually start NTPrime
with the system running "normally"? If the answer to _either_ of the
last two questions is "no", then NTPrime isn't the problem.
Does the incidence of the problem coincide with a great deal of disk
activity, which doesn't die away after at most one minute but
continues indefinitely? If so, this is a clear indication that the
problem is being caused by a shortage of memory.
How much memory is there in your system? If you're running NTPrime,
the P-1 memory allocation isn't a factor since NTPrime v20 isn't yet
released. However, if you're running LL tests on _big_ exponents,
memory shortage could be crucial. NTPrime is going to use somewhere
between 16 and 20 megabytes of _physical_ memory to run LL tests on
"10 million digit" exponents. I wouldn't try to run LL tests on
exponents much bigger than about 10 million on a system running NT
with 64 MB (or less) of memory, unless there really was only a very
occasional need for the system to run anything else. If you're tight
on memory, you may find that switching to double-checking assignments
cures your problem.
I take it that you're not trying to do anything daft like running
more instances of NTPrime/Prime95 (in total) than you have processors
on the system. Running like this causes inefficiencies due to excess
task switching and also consumes memory to no good purpose.
Also I still think it's worth checking for unwanted intrusions
(BackOrifice seems fashionable at the moment) and also removing any
services like FindFast which appear to have very little value -
certainly FindFast can cause so much disk activity that things pretty
well grind to a halt for a while - _except_ CPU soak programs like
Prime95/NTPrime which can use the cycles which would otherwise be
wasted since the other, higher-priority processes are all waiting for
disk activity to finish. This is a _big_ price to pay for something
which _might_ (if you're exceptionally fortunate) help you to open a
MS Office document a split second faster.
BTW it's perfectly normal for the first instance of opening e.g.
Windows Explorer to be slower than usual (though 20 seconds certainly
sounds excessive!), since none of the various DLLs etc. required will
be already in memory. On my system, during the first 5 minutes or so
following a system boot, everything is unusually slow due to the
activity of an anti-virus scanner. I'm prepared to live with this for
the extra security it offers.
Defragmenting the disk can make a major improvement to the speed at
which applications open - you really need to use a quality
defragmenter like Diskeeper (Executive Software) since you want to
get the swap/page file and the index (directory) files (plus the MFT
on a NTFS volume) properly organized, as well making the data files
contiguous. I also find that it helps to fix the page/swap file size
(Control Panel/System/Performance) so that the minimum & maximum
sizes are the same; the maximum of 128 MB and twice the system memory
seems to be a sensible value to start with, if your system really
needs more it will let you know! The idea is to prevent the page/swap
file becoming excessively fragmented by cumulative allocation of
extra chunks.
Hope this is of some use to you!
Regards
Brian Beesley
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