Experimental Physics and
Industrial Control System

Lifang Zheng <[email protected]> · Thu, 07 Dec 2000 09:05:53 +0800

Dear all,

I want to test Dr.Dalesio mentioned throughputs:

> >     Performance:
> >     68040 over 10 Mbit Ethernet
> >     Gets
> >      Propagation Delay  2  mS
> >      Throughput  7.8K /sec
> >     Puts
> >      Propagation Delay  1 mS
> >      Throughput  17K /sec
> >     Monitors
> >      Propagation Delay   Dependent
> >      Throughput  10K / sec

I got GET throughput is 7.3K/s. But for PUT, I only got 7.8K/s, much
more less than Bob's. I am not sure if I did the right way. The
followings are my source codes.

I have two questions:
1. What is propagation delay?
2. Because monitor only works when the channel value is changed, does
10K/s of monitor throughput mean the record should be processed in less
than 0.1ms?

I will appreciate if somebody could give me some advice & suggestions.

Best regards,

Lifang

/***********************************************************/
 #include <stdlib.h>
 #include <stdio.h>
 #include <time.h>

 #include <cadef.h>

 #define USAGE "usage: ezee <PV name>  MAXLOOP"

 int main(int argc, char **argv)
 {
         register int i;
         chid chan;
         dbr_string_t strval;
         int  status, MAXLOOP=1000000;
         dbr_float_t value[1000000];
         struct timespec times1, times2;
         double tm1, tm2, rate;

         if(argc != 3){
                 printf("%s\n", USAGE);
                 exit(-1);
         }

         status = ca_task_initialize();
         SEVCHK(status, "Unable to initialize");
         if (status != ECA_NORMAL)
                 exit(-1);

         status = ca_search(argv[1], &chan);

         if (status != ECA_NORMAL){
                 printf("problem establishing connection to
%s.",argv[1]);
                 exit(-1);
         }

         status = ca_pend_io(1.0);

         if (status != ECA_NORMAL){
                 printf("%s: Not Found\n", argv[1]);
                 exit(-1);
         }

        MAXLOOP = atoi(argv[2]);

         for(i=0; i<MAXLOOP; i++)value[i] = i;

        clock_gettime(CLOCK_REALTIME, &times1);

        for(i = 0; i < MAXLOOP; i++)
         {
                 status = ca_rput(chan, &value[i]);
                 SEVCHK(status, "Error in call to ca_bput()");
         }

         status = ca_pend_io(1000.0);
         clock_gettime(CLOCK_REALTIME, &times2);

         if (status != ECA_NORMAL)
         {
                 printf("%s: Get Timed Out\n", argv[1]);
                exit(-1);
         }

         tm2 = 1.0*times2.tv_sec + times2.tv_nsec*1.0e-9;
         tm1 = 1.0*times1.tv_sec + times1.tv_nsec*1.0e-9;
         rate = 1.0*MAXLOOP/(tm2-tm1);

         printf("tm2: %f\n", tm2);
         printf("tm1: %f\n", tm1);
         printf("tm2-tm1: %f  rate: %f \n", tm2-tm1, rate);

         ca_task_exit();
         return(0);
 }

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System