The windows server operates the database very slowly to process records.

When receiving a report, a windows server server is particularly slow to query the database across network segments. We investigate from the aspects of network and system respectively.

1. Ping the destination address from the windows server server for a long time, the delay and jitter are normal, and there is nothing wrong with the network.

2. Check the CPU and memory usage of the windows server server. CPU and memory are running normally without excessive CPU and memory exhaustion.

3. The file is copied by sharing between the windows server server and the destination machine, and it is found that the speed cannot go up.

4. Find a windows machine in the same network segment as the windows server server, and copy the files at the speed of 5MBPS. Judging from this, there is no problem with reading and writing the hard disk of the server itself and connecting to the local area network.

5. Later, using wireshark to grab packets, it was found that there were a large number of tcp ack retransmissions and tcp out-of-order errors.

This application used to have a server that read data and copied files normally. Later, by comparison, it was found that the original server was windows server 2008 R2 enterprise, and now this server is windows server 2008 R2 standard. In the mood of giving it a try, change the standand of the server to the enterprise version, and then the test is normal. In the end, no problem was found, but after the version was replaced, the problem was solved.