Re: [plt-dev] JFYI editor performance note

[John Clements]

On Apr 17, 2009, at 2:05 PM, Matthew Flatt wrote:

At Fri, 17 Apr 2009 13:48:57 -0700, John Clements wrote:

On my ancient PPC G5 cheese-grater, svn head editors are very very
slow relative to 4.1.4. I note the following things:


type 160 characters quickly, it takes svn head 15 seconds to get them

as fast as I personally can type them, in this case 154 chars in 5
seconds.  So, this is at least 3 times as fast, possibly much more.

1) I can get *way* ahead of the keystroke buffer. In particular, if I all onto the screen. In 4.1.4, on the other hand, DrScheme takes them

From my measurements, many core editor operations now take 6-10 times

as long as before. Even, the operation of inserting a character
shouldn't take 1/10 second. I'll investigate into this example
specifically.

#lang scheme

(require redex)

;; going to just one argument.

(define-language lamv
  (e (e e ...) (if0 e e e) x v)
  (v (lam (x) e) true false nand)
  (E (E e) (v E) (if0 E e e) hole)
  (x (variable-except lam true false nand if0)))

(define red
  (reduction-relation
   lamv
   (--> (in-hole E (if0 true e_1 e_2))
        (in-hole E e_1)
        "if0t")
   (--> (in-hole E (if0 false e_1 e_2))
        (in-hole E e_2)
        "if0f")
   ;; gets stuck otherwise?
   (--> (in-hole E (nand true true))
        (in-hole E false)
        "nandt")
   (--> (in-hole E (nand e_1 e_2))
        (in-hole E true)
        "nandf"
        (side-condition (and (member (term e_1) '(true false))
                             (member (term e_2) '(true false)))))
   (--> (in-hole E ((lam (x) e) v))
        (in-hole E (subst (x v) e))
        "beta-v")))

FWIW, I see that this does depend on the content of the buffer. I observe the behavior I described when typing at position zero in with this in the buffer:

smime.p7s
Description: S/MIME cryptographic signature

_________________________________________________
  For list-related administrative tasks:
  http://list.cs.brown.edu/mailman/listinfo/plt-dev