单机上万客户端连接
转： http://www.metabrew.com/article/a-million-user-comet-application-with-mochiweb-part-3
#include <sys/types.h>#include <sys/time.h>#include <sys/queue.h>#include <stdlib.h>#include <err.h>#include <event.h>#include <evhttp.h>#include <unistd.h>#include <stdio.h>#include <sys/socket.h>#include <netinet/in.h>#include <time.h>#include <pthread.h>#define BUFSIZE 4096#define NUMCONNS 62000#define SERVERADDR "74.125.71.99"#define SERVERPORT 80#define SLEEP_MS 10char buf[BUFSIZE];int bytes_recvd = 0;int chunks_recvd = 0;int closed = 0;int connected = 0;// called per chunk receivedvoid chunkcb(struct evhttp_request * req, void * arg){ int s = evbuffer_remove( req->input_buffer, &buf, BUFSIZE ); //printf("Read %d bytes: %s\n", s, &buf); bytes_recvd += s; chunks_recvd++; if(connected >= NUMCONNS && chunks_recvd%10000==0) printf(">Chunks: %d\tBytes: %d\tClosed: %d\n", chunks_recvd, bytes_recvd, closed);}// gets called when request completesvoid reqcb(struct evhttp_request * req, void * arg){ closed++;}int main(int argc, char **argv){ event_init(); struct evhttp *evhttp_connection; struct evhttp_request *evhttp_request; char addr[16]; char path[32]; // eg: "/test/123" int i,octet; for(octet=1; octet<=17; octet++){ sprintf(&addr, "172.17.3.%d", octet); for(i=1;i<=NUMCONNS;i++) { evhttp_connection = evhttp_connection_new(SERVERADDR, SERVERPORT); evhttp_connection_set_local_address(evhttp_connection, &addr); evhttp_set_timeout(evhttp_connection, 864000); // 10 day timeout evhttp_request = evhttp_request_new(reqcb, NULL); evhttp_request->chunk_cb = chunkcb; sprintf(&path, "/?%d", ++connected); if(i%100==0) printf("Req: %s\t->\t%s\n", addr, &path); evhttp_make_request( evhttp_connection, evhttp_request, EVHTTP_REQ_GET, path ); evhttp_connection_set_timeout(evhttp_request->evcon, 864000); event_loop( EVLOOP_NONBLOCK ); if( connected % 200 == 0 ) printf("\nChunks: %d\tBytes: %d\tClosed: %d\n", chunks_recvd, bytes_recvd, closed); usleep(SLEEP_MS*1000); } } event_dispatch(); return 0;}$ gcc -o httpclient httpclient.c -levent$ ./httpclient
# netstat -n | awk '/^tcp/ {t[$NF]++}END{for(state in t){print state, t[state]} }'