Re: Virtual serial drive

[Riccardo <rigreco.grc@gmail.com>]

Il giorno venerdì 14 settembre 2012 04:53:27 UTC+2, schmidtd ha scritto:
> On 9/11/2012 3:25 AM, aiiadict@gmail.com wrote:
> 
> > On Monday, September 10, 2012 7:04:17 PM UTC-7, schmidtd wrote:
> 
> >>
> 
> >> http://adtpro.sourceforge.net/vdrive.html
> 
> >
> 
> > What is transfer rate of 1)serial 2)ethernet ?
> 
> 
> 
> I was scared to look.  But...
> 
> 
> 
> All times in seconds, measured three times via stopwatch, averaged 
> 
> together.  Tests run on a Platinum IIe under ProDOS 1.9 as shipped on 
> 
> the VSDRIVE disk.  Host was a 2009 iMac with Prolific USB adapter. 
> 
> Virtual and real disks were erased after each write run.  $6C00 bytes 
> 
> was the largest single hunk of memory that could be re-read without 
> 
> stepping on anything (i.e. the fat Ethernet driver).
> 
> 
> 
> Disk II in slot 6
> 
> BSAVE A800L6C00,A$800,L$6C00
> 
> 17.5 (1,609.1 bytes/s)
> 
> BLOAD A800L6C00
> 
> 4.6 (6,121.7 bytes/s)
> 
> 
> 
> Super Serial in slot 2
> 
> BSAVE A800L6C00,A$800,L$6C00
> 
> 5.6 (5,028.6 bytes/s)
> 
> BLOAD A800L6C00
> 
> 3.7 (7,610.8 bytes/s)
> 
> 
> 
> Uthernet in slot 3
> 
> BSAVE A800L6C00,A$800,L$6C00
> 
> 4.6  (6,121.7 bytes/s)
> 
> BLOAD A800L6C00
> 
> 2.2 (12,800 bytes/s)
> 
> 
> 
> CFFA3000 in slot 7 (virtual image on CF card)
> 
> BSAVE A800L6C00,A$800,L$6C00
> 
> 1.7 (16,564.7 bytes/s)
> 
> BLOAD A800L6C00
> 
> 0.5* (56,320 bytes/s)
> 
> *Probably beyond my ability to reasonably measure
> 
> 
> 
> So, moral of the story - faster than the Disk II, slower than storage on 
> 
> the bus, Ethernet is faster than serial.

It's very great,
it confirm my user impression, don't forget that :
1) Real disk: load/save time= time to access file (positioning mechanical head)+time to read/write (depending to disk speed)+ time to transfer data (depend of link interfacing disk);
2) Virtual disk: load/save time = time to access and read/write is near to zero (electronic) + time to transfer data (depend of link connection to PC/MAC);
Riccardo.