tcp ip - TCP/IP back to back read and write taking too long -

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i trying transfer messages using tcp/ip. found if 1 party acts sender , other party acts receiver, transfer fast. if 2 parties switch roles more often, becomes slow.

to specific, operation takes 6 ms:

**server:**  (int = 0; < 5000; i++){     read(connfd, s1, 128);       read(connfd, s2, 128); }  **client:**  (int = 0; < 5000; i++){     write(sockfd, s1, 128);      write(sockfd, s2, 128); }

and operation takes 98 ms: 

**server:**  (int = 0; < 5000; i++){     read(connfd, s1, 128);       write(connfd, s2, 128); }  **client:**  (int = 0; < 5000; i++){     write(sockfd, s1, 128);      read(sockfd, s2, 128); }

is there way reduce delay?


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