brain dump

from Jargon File (4.4.4, 14 Aug 2003)

brain dump
 n.

   [common] The act of telling someone everything one knows about a
   particular topic or project. Typically used when someone is going to
   let a new party maintain a piece of code. Conceptually analogous to an
   operating system {core dump} in that it saves a lot of useful {state}
   before an exit. "You'll have to give me a brain dump on FOOBAR before
   you start your new job at HackerCorp." See {core dump} (sense 4). At
   Sun, this is also known as TOI (transfer of information).

from The Free On-line Dictionary of Computing (8 July 2008)

brain dump

   (The act of telling someone) everything one knows about a
   particular topic.  Typically used when someone is going to let
   a new party maintain a piece of code.  Conceptually analogous
   to an operating system {core dump} in that it saves a lot of
   useful {state} before an exit.  "You'll have to give me a
   brain dump on FOOBAR before you start your new job at
   HackerCorp."  At Sun, this is also known as "TOI" (transfer of
   information).

   [{Jargon File}]