Performance optimization in av::fixup - use buffered IO, not mapped file

[Daniel Colascione]

On 12/10/2012 7:51 PM, Daniel Colascione wrote:
> The key to generating a binary that repros the problem is to unexec emacs, then
> try to repro with that generated binary, not a copy of it.

The real explanation is a lot simpler: the binary is sparse. When you create a
file mapping object for a sparse file, Windows discards all cached pages for
that file. It makes sense that compilers (and Emacs unexec) would create sparse
files as they seek around inside their outputs.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 258 bytes
Desc: OpenPGP digital signature
URL: <http://cygwin.com/pipermail/cygwin-developers/attachments/20121212/5575edfa/attachment.sig>