Don't create a 2mb stack object

Change-Id: I24001deb436b4f5859e8e58400fbff176253514e
Reviewed-on: http://review.couchbase.org/42841
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>