On Fri, Jun 17, 2016 at 11:44:26AM +0200, Julia Lawall wrote: > I'm not sure that this is worth it. It adds a dependency on a tool that > seems not to be well maintained. In terms of Coccinelle, I'm not sure > that it gives a big benefit. > > Attached is a graph showing the file selection time for Coccinelle for a > selection of fairly complex semantic patches. Coccigrep is just a > line-by-line regexp search implemented in ocaml, gitgrep uses git grep. > In most cases, glimpse is clearly faster. > > On the other hand, it seems that glimpse often selects more files. > Sometimes a few more, eg 16 vs 14, and sometimes quite a lot more, eg 538 > vs 236. I suspect that this is because glimpse considers _ to be a space, > and thus it can have many false positives. There are, however, a few > cases where glimpse also selects fewer files. > > The file processing time (ie parsing the file, searching for, matches of > the semantic patch in the file, and performing the transformation) is > normally much higher than the file selection time. > > So it seems that git grep is currently a better option for the kernel.
Great, thanks, consider this patch dropped, do we want the heuristics for the cache index in place though or should I drop that as well ? Luis
