F5 FastL4 but need HTTP header insert

That's progress, at least. You should enable compression on the origin load balancers (on the other side of the WAN link) and see if that helps.

 

 

The original load balancers do have compression turned on if the client requests it; the F5 appears to disable this or block it (just a guess; with compression disabled, the content is always clear text, even when requested with headers).

 

 

It appears that FastL4 is not any "better" than using http-wan-optimised and is worse because we cannot do the header insert for the client IP. Using FastHTTP is frustrating because it looks like we cannot use Irules or oneconnect (oneconnect saves us .2 - .3 seconds across the Atlantic).

 

 

Barring any further ideas, we are going to turn on compression anyway because we feel that compression is the correct setting, even if it causes some machine-measurable slowness.