Re: [PATCH 1/3] use struct sha1_array in diff_tree_combined()
From: Jeff King <hidden>
Date: 2016-06-15 22:52:40
On Sat, Dec 17, 2011 at 12:16:32PM +0100, René Scharfe wrote:
quoted
The original code is slightly more efficient, as it is able to use a single malloc (because it knows the number of entries ahead of time). It probably doesn't make a difference, but we could also add a sha1_array_grow() for this case.[...] We coulddo that, yes. In the case above we have the number already, in the other cases we'd have to count. But I don't think it's worth it here. ALLOC_GROW gives us 24 entries initially, which should be enough in most cases -- I'm not sure I want to see combined diff of that many tree. And 24 times 20 bytes is small enough to not cause any memory allocation issues.
You're right. I was blindly looking at the conversion without thinking about the context. Of course if you have just a few items, it's going to be irrelevant (my initial refactoring of sha1_array was to help speed up a hundreds-of-thousands of sha1s case, so I think that put me in the mindset of a large list). Sorry for the noise. -Peff