> In Differ, merged diffs are repeatedly calculated whenever we iterate > over changes. The merged versions of diffs can theoretically differ, > as the underlying text is passed in on each call. However, this text > always ends up being the raw file text, and we always update our diffs > whenever this text changes. As such, we can cache the merged version > of our diffs by disallowing the effectively unused texts argument. > > I'm attaching two patches, the first of which implements this caching > of merged diffs, and the second of which provides a short-circuit for > two-way comparisons. On two-way diffs, these patches provide a very > slight speed improvement; on three-way diffs, the speed-up is easily > measurable -- around 5% in a few quick tests based on scrolling > through a three-way source file comparison.
Thats a good idea. I've semi-deliberately not changed any of the diffing code in ages because I've always intended to rewrite it with an asynchronous interface. I think this is the only way to get acceptable performance on large files/large change blocks. It's reasonable then to put the diff computation & most of the i/o in a subprocess, which would make the ui much more responsive. Stephen. _______________________________________________ meld-list mailing list meld-list@gnome.org http://mail.gnome.org/mailman/listinfo/meld-list
