[Moosefs-users] changelog on Metalogger not flush to disk instantly

[郑. <zh...@uc...>]

Dear Michał,

I found the changelog on Metalogger machine not flush to disk instantly. I dig into the code, and found there miss a fflush in mfs-1.6.17/mfsmetalogger/masterconn.c:185.

142 void masterconn_metachanges_log(masterconn *eptr,const uint8_t *data,uint32_t length) {
143     char logname1[100],logname2[100];
.....
182     data++;
183     version = get64bit(&data);
184     if (eptr->logfd) {
185         fprintf(eptr->logfd,"%"PRIu64": %s\n",version,data);
              fflush(eptr->logfd);  //missed
186     } else {
187         syslog(LOG_NOTICE,"lost MFS change %"PRIu64": %s",version,data);
188     } 
189 }   

I think this maybe a tiny bug, because the changelog is so important to the metalogger, we need to flush it instantly.

Best regards!

Haihong Zheng from China