Disk IO scheduling in guest kernel slow

Greetings

If I perform certain IO operations (such as deleting files) all other io operations nearly starve.

While deleting a 1gb file on the background, listing home directory files, ls ~ takes 10-15 seconds to complete:

Example:

create a file:

% dd if=/dev/zero of=testfile bs=1024M count=1

delete it on the background:

% rm testfile&

time ls of ~ (32 items on ~, mostly folders)

% time ls

…

ls -F --color=always 0.00s user 0.00s system 0% cpu 14.071 total

Is this typical?

Is there another disk IO scheduler available for install as a kernel module?