Any simple / quick ways to improve web traffic

What are the Proxy Buffer Low and High values?

 

 

First thing I'd do is bump up both window sizes to 65535.

 

 

Next I'd enable the Proxy Maximum Segment, and probably Proxy Options too. I had a situation a couple of weeks ago where I discovered that our firewall was reducing the MSS advertised by the client (1460 bytes) before it hit the LTM (1380 bytes). But without Proxy Maximum Segment, the LTM advertised a full segment size (1460) to the server. The server sent 1460 response packets to the LTM, but the LTM split them up into two packets before sending them on to the client - one 1380 bytes and another one 80 bytes. I had assumed that the LTM would re-assemble the packets into full 1480 byte packets, but it did not. It simply split up each packet that was received by the server. By enabling the Proxy Maximum Segment option, it forced the server to send smaller packets (1380) before sending them to the LTM. The LTM then just forwarded them on.

 

 

Next thing I see is Nagle. When you have Nagle enabled on the LTM, this will conflict with the Delayed Acknowledgements setting on clients (which is enabled on Windows and every other OS I've seen). When the LTM is sending data and it receives a packet which is not full-sized, the LTM will sit on it until a) it receives enough data to make a full-sized packet or b) it receives an ack from the client. But the client may be waiting for more data from the LTM because of the Delayed Acknowledgement algoritm causing a deadlock. This is a good description of the problem.

 

 

http://www.stuartcheshire.org/papers/NagleDelayedAck/

 

 

Also over the past couple of days I've been studying the effects of disabling Slow Start. It appears to me that enabled Slow Start results in a situation where there the LTM will only allow a small, limited number (3-4) of outstanding packets on the wire before it sits and waits for an acknowledgement. This slows down throughput tremendously. However with Slow Start disabled, the LTM looks like it tries to completely fill the client's Receive Window before stopping and waiting. Someone will probably try to correct me my description of this particular setting, but that sure looks like the effect to me in the tcpdumps I've done.