performance/quick-read: make a comment more explicit.
performance/quick-read: make a comment more explicit.

Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 273 (Code review and optimize quick-read)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=273

Kaushikbv/Gluster,Kaushikbv/Gluster,Kaushikbv/Gluster