[RTTY] FYI - Multiple MMTTY copies with ONE soundcard

Jerry Flanders jeflanders at comcast.net
Tue Feb 22 10:47:31 EST 2005


After Jerry Pixton explained that XP will permit several sound card 
applications to run simultaneously, I started thinking that it might be 
useful sometimes to have multiple instances of a soundcard TU like MMTTY 
running in order to copy the signal under several different "profiles" 
simultaneously. Sometimes when signals are marginal in a contest I have to 
mentally combine outputs from several different "receive only" TUs to 
extract the exchange data.

So, the obvious question: How many instances of MMTTY can a modern computer 
run?

It was easy to set up a test: On my 1.5 GHz P4 512 GB machine running XP 
Professional SP2, I started up 6 instances of MMTTY. I set up each 
differently - several profiles, two printing reverse copy, two with a 
notch, one with BPF on.

I wondered how well my new cheapie AMD Sempron 3000+ (2 GHz) 256MB XP Home 
machine would compare, so started up the same test on it.

XP's "Process Monitor" utility reported average processor usage. I removed 
one copy and waited 2 minutes for each step.

All MMTTYs appeared to run well, each printing its independent best guess 
of the signal. Live RTTY signals were present only part of the time.

The performance monitor readings are:

	%Processor time       		Copies of MMTTY
Pentium 4		Sempron
34				12		6
25				10		5
23				08		4
12				06		3
10				04		2
05				02		1
00				00		0

If you smooth out the steps, it looks like the P4 takes 5% for each copy 
whereas the Sempron takes 2%.

Writelog was not running at the time, but I wouldn't expect it to add much 
load. Looks like modern computers can do MUCH more than we usually ask of them.

Please forward this to the MMTTY reflector (one copy). I don't subscribe to it.

Jerry W4UK



More information about the RTTY mailing list