Read-sequence is slow?

[Raymond Toy]

I have this routine:

|(defun slurp-bytes (filename) "Return the entire contents of FILENAME 
as a (unsigned-byte 8) vector. Results are cached in *bytes-cache* so 
each file is read only once." (or (gethash filename *bytes-cache*) (setf 
(gethash filename *bytes-cache*) (with-open-file (s filename :direction 
:input :element-type '(unsigned-byte 8)) (let* ((len (file-length s)) 
(buf (make-array len :element-type '(unsigned-byte 8)))) (read-sequence 
buf s) buf))))) |

When reading maxima.info-1 (1030671 bytes), it takes a very long time 
(several seconds). Is there anyway to speed this up? I would have 
expected reading a bunch of bytes from a file via read-sequence would be 
very fast.

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