How to use Linux ld_preload to mock the connection to the db or loadgen

[RobertHenry6bev]

I would like to make a mock postgres db server by intercepting all relevant syscalls from/to the webserver process. Likewise, I want to mock incoming http requests from/to the webserver.

For the purposes of my test, I want to minimize the time spent in the kernel, and most of the network traffic is "the same".

Has anyone done this using the ld_preload mechanism on Linux, wherein specific syscalls can be hooked and then monitored or mocked?