>You dont need an RTOS to sustain 2-4KB/sec to a storage device.  The OS is
>hardly the bottleneck if you cant burn a CD properly.

The data rate is faster than that.  For a 8X CDRW, it's 1.2MB/sec.  If your
CDRW buffer is 2MB, you have less than 2 seconds of margin, then you have a
coaster CD.

For example, lets say you have an open session of Protel 99SE.  It autosaves
every 10 minutes or so.  During the autosave, it hogs the CPU.  If you were
burning a CD during that time, you would end up with a coaster.

You can blame this any number of things (Protel is a hog, crappy CD burner,
buggy CD burner software, etc.), but the reality is that the OS is not a
real-time OS, because it has no way to guarantee that a critical thread will
execute within a bounded latency.  This is why we have to "baby" our CD
burning process.  Maybe your SCSI CDRW's don't have this problem because
they have huge buffers?  They should, considering the $$$ you paid for them.

Real-time will someday come to the common OS (Windows, Linux, etc.).  Until
then, people will foolishly keep buying ever faster machines hoping to
overcome latency through sheer brute force.

Best regards,
Ivan Baggett
Bagotronix Inc.
website:  www.bagotronix.com


----- Original Message -----
From: "Matt Daggett" <[EMAIL PROTECTED]>
To: "Protel EDA Forum" <[EMAIL PROTECTED]>
Sent: Wednesday, August 28, 2002 9:26 AM
Subject: Re: [PEDA] SCSI v IDE & IBM Deathstars (was Protel vs. DirectCD)


You dont need an RTOS to sustain 2-4KB/sec to a storage device.  The OS is
hardly the bottleneck if you cant burn a CD properly.




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