Slow response via VS than direct - why?

Hello F5 folks,

 

I have a very simple Virtual Server configuration with clientssl and http profiles and source_addr persistence.

 

Users of the thick-client are complaining that responses are slower via VS than via direct connection to the back-end servers (load-balanced by the VS).

 

Snooping on the server-side (ie. cleartext between F5 and back-end server), I've only noticed two unusual traffic characteristics:

 

1. server response contains "Content-Type: text/html" header but the actual entity-payload is binary (I'd say 'application/octet-stream' is more appropriate); and

    

2. the client's requests contain "Expect: 100-continue" header and await "HTTP/1.1 100 Continue" response before sending entity-payload.

    

Can either of these cause slow-down that I'm experiencing?

 

R's, Alex