The bsd_tree and bsd_queue data structures are header only implementations taken from the BSD distribution. Descriptions for them can be found at:
The icl_hash and icl_list are fairly basic implementations, developed initially for an earlier project (GridSolve) and then reused here. The implementation are very simple and should be fairly reasonable to read in the code and headers.
There is a QUARK specific site http://icl.cs.utk.edu/quark/
There is a QUARK users guide that will give you some idea of how to use QUARK.
QUARK does not do well with small quantities of data, because the relative overheads of the runtime become large when compared to the computation. So, for a double precision matrix multiplication, a tile size of 220x220 will perform much better than a small tile size. However, the there is no specific tile size... it depends on the machine and algorithm. We are planning to do work on autotuning to determine the appropriate tile sizes automatically, but for the present, a user simply needs to guess/tune manually.
The window size is not as important for the performance. There is a environment variable (QUARK_UNROLL_TASKS_PER_THREAD) that can be set to change the window size from the default, but I doubt that you need to alter it.
There is very limited user control over the work stealing. You can prevent a task from being stolen by binding it to a specific thread or set of threads, but that it all.
As Mathieu said, the numactl comment is out of date.
However, if you have no better way to distribute your data, it is better than nothing!
QUARK work stealing is not really cache aware. There is an ordering to the threads determined by the machine layout (and discovered by the hwloc library if it is configured and installed). QUARK steals from the threads in that order, but this may not correspond to nearest neighbors/local caches. We need to fix that!
There has been discussion to see if QUARK could do power aware scheduling, but this has not gone very far yet. If you have an example of power policies that would be of interest, please let us know.
Hope this helps,