From: kludge@panix.com   
      
   In article ,   
   Lawrence D'Oliveiro   wrote:   
   >On Sun, 4 May 2025 20:53:42 -0400 (EDT), Scott Dorsey wrote:   
   >   
   >> You should check out Martin's "Design of Real-Time Computer Systems"   
   >> which was written in the early days of SAABRE and other transaction   
   >> processing systems.   
   >   
   >Their idea of real time was responding in a few seconds, before the user   
   >got frustrated enough to hit SEND again.   
      
   Today we would call those "interactive systems," yes.  Not the same as   
   true realtime systems with deadlines.   
      
   >Meanwhile, Linux recently mainlined the PREEMPT_RT patches, where the   
   >definition of real time is being able to provide sub-millisecond   
   >response to playing or recording sound samples for pro audio.   
      
   That's still not hard realtime at all, but it gives you reduced latency,   
   realtime scheduling, and the ability to preempt kernel threads.  That   
   latter one has become a big deal since som much crap has been rolled into   
   the kernel.   
      
   But what they mean by "RT" isn't what hard realtime people mean by "RT"   
   which has nothing to do with what the transaction processing guys meant   
   as "RT."  Do not get hung up on words, especially when people use the same   
   words for rather different concepts.   
   --scott   
      
   --   
   "C'est un Nagra. C'est suisse, et tres, tres precis."   
      
   --- SoupGate-DOS v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)