Re: BASE_PURESIZE

[Stephen J. Turnbull]

Juanma Barranquero writes:
 > On Fri, Oct 23, 2009 at 13:00, Eli Zaretskii <address@hidden> wrote:
 > 
 > > I looked at the values of pure_size vs pure_bytes_used in several
 > > builds on several platforms, and I see that we are wasting at least
 > > 130KB:
[...]
 > on Windows I get
[...]
 > or about 252 KiB wasted.

Three comments:

1.  XEmacs abandoned pure space years ago on the assumption that (bugs
    aside) copy-on-write means that dumped text will be shared anyway.
    Is that incorrect?

2.  252 KiB is not negligible, I suppose, but these days the systems
    Emacs runs on typically sport >1GB of memory, and since that's
    pure space even with multiple instances of Emacs running that is
    all that will be wasted ever.

3.  To save the space, dump twice, the second time using the precise
    number you can measure from the first try.  Unlike the Lisp
    compilation stage, this takes less than an extra minute IIRC.  If
    you still care about the extra time, make the second dump part of
    the install target.