It turns out that libc malloc can return an allocation of a different size on requests of the same size.
this means that matching MEMORY USAGE of one key to another copy of the same data can fail.
Solution:
Keep running the test that calls MEMORY USAGE, but ignore the response.
We do that by introducing a new utility function to get the memory usage, which always returns 1
when the allocator is not jemalloc.
Other changes:
Some formatting for datatype2.tcl
Co-authored-by: Oran Agra <oran@redislabs.com>