This node is only presented for the profiled process.
JIT memory is the memory used by the JIT-compiled code of the process. The profiler tries to match the memory with the module (.exe or .dll) that contains the code (or actually the IL code that was JITted). If it succeeds, the memory is presented under the Code node using the name of the matched module; otherwise the memory is presented as “<Other>.”
If low-impact profiling is enabled, then JIT memory will give information about how JITted code is shared between processes. If low-impact profiling is not enabled, all JITted code will be private to the profiled process, since the code has been modified by the profiler.