Error: cannot allocate vector of size x Gb (64-bit ... yet again)

Hello,

I am facing the dreaded "Error: cannot allocate vector of size x Gb" and
don't understand
enough about R (or operating system) memory management to diagnose and
solve the problem
-- despite studying previous posts and relevant R help -- e.g.:

"Error messages beginning cannot allocate vector of size indicate a
failure to obtain memory,
either because the size exceeded the address-space limit for a process
or, more likely,
because the system was unable to provide the memory.
[...] On all builds of R, the maximum length (number of elements)
of a vector is 2^31 - 1 ~ 2*10^9, as lengths are stored as signed integers.
In addition, the storage space cannot exceed the address limit."
- from Memory-limits {Base}

Simple question: Given 64-bit R (AMD64 Linux) with a ulimit of
"unlimited", can the size of an R object exceed the amount of availlable
RAM
memory?

Empirically my system with 4Gb RAM and ample Swap, is failing:

Error: cannot allocate vector of size x Gb (64-bit ... yet again)

Thread (3 messages)