Fix for slow telnet on 4.1 ( Windows )

[gpontis]

This subject has been discussed several times for earlier releases of MQX, but I never saw a clear-cut fix. My 4.1 app supports a telnet interface but was painfully slow. The fix was to modify the rtcs library slightly to disable the Nagle algorithm for the Telnet server. In the RTCS project, under apps, edit the file telnsrv.c. Around line 280 add the code to change this option:

   // Disable nagle algorithm for much faster performance with Windows clients

   option = 1;  

   error = setsockopt(telnetsrv_context.LISTENSOCK, SOL_TCP, OPT_NO_NAGLE_ALGORITHM, &option, sizeof(option));

   if (error) {

      RTCS_task_exit(creator, error);

   }

George

[matthewkendall]

A while ago I did very much the same thing, but I made it an option rather than hard-coding it off. I added this to user_config.h

#define TELNETDCFG_NO_NAGLE_ALGORITHM            1

Then in telnsrv.c, in TELNETSRV_task() at the beginning where the options are being set up, I added:

   option = TELNETDCFG_NO_NAGLE_ALGORITHM;
   error = setsockopt(telnetsrv_context.LISTENSOCK, SOL_TCP, OPT_NO_NAGLE_ALGORITHM, &option, sizeof(option));
   if (error) {
      RTCS_task_exit(creator, error);
   }

To provide a default, add the following to rtcscfg.h:

/*
** MGCT: <option type="bool"/>
*/
#ifndef TELNETDCFG_NO_NAGLE_ALGORITHM
   #define TELNETDCFG_NO_NAGLE_ALGORITHM 0
#endif

I believe that also has the effect of making the option show up in the GUI editor for user_config.h on the RTCS tab.