windows-server-2008-r2 – 需要超低延迟,如何最小化？

http://download.microsoft.com/download/6/B/2/6B2EBD3A-302E-4553-AC00-9885BBF31E21/Perf-tun-srv-R2.docx

该文档中有136页性能调整指南.

您可能还会从support.microsoft.com/kb/214397/en-us获得一些有趣的信息

您也可以尝试禁用Windows过滤平台,这通常不建议使用,但它可能有助于缩短I / O在操作系统中的运行时间.

您还拥有微软已经融入Windows的一系列技术,这些技术专门针对低延迟网络,但其中大部分都是2012年的具体改进,而不是2008 R2：

http://technet.microsoft.com/en-us/library/hh831415.aspx

1. Data Center Bridging

2. Data Center Transmission Control Protocol (DCTCP)

3. Kernel Mode Remote Direct Memory Access (kRDMA)

4. Network Interface Card (NIC) Teaming

5. NetworkDirect

6. Receive Segment Coalescing (RSC)

7. Receive Side Scaling (RSS)

8. Registered Input/Output (RIO) API Extensions

9. Transmission Control Protocol (TCP) Loopback Optimization

10. Low Latency Workloads Management and Operations

但是只有这么多,你才能用软件调整.只需将硬件升级到Infiniband/RDMA over Converged Ethernet,您就可以通过在Windows注册表中翻转位来大幅减少延迟,这是您永远无法实现的.

最后,这里有一些更直接的东西answering your question about delayed ACK.我不知道这是不是你的问题,但是：

Subkey:
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesTcpipParametersInterfaces

Entry: TcpAckFrequency

Value Type: REG_DWORD,number Valid Range: 0-255 Default: 2
Description: Specifies the number of ACKs that will be outstanding
before the delayed ACK timer is ignored. Microsoft does not recommend
changing the default value without careful study of the environment.

If you set the value to 1,every packet is acknowledged immediately because there is only one outstanding TCP ACK as a segment is just received. The value of 0 (zero) is not valid and is treated as the default,2. The only time the ACK number is 0 is when a segment is not received and the host is not going to acknowledge the data.