# [PATCH 0/6] packed deltas with offset to base instead of sha1 4 messages from 2006-09-21 to 2006-09-22. Participants: Nicolas Pitre, Junio C Hamano, Shawn Pearce. Thread: https://gitlist.dev/t/5628 ## Nicolas Pitre, 2006-09-21 04:04 Subject: [PATCH 0/6] packed deltas with offset to base instead of sha1 Message-ID: URL: https://gitlist.dev/e/Pine.LNX.4.64.0609202350450.2627%40xanadu.home ``` The following patches are the result of my work to allow deltas to have their base specified as an offset within a pack instead of a 20 byte sha1. This turned to be somewhat more involved than I originally expected. Given the relative pack reduction resulting from that, I might have decided against doing this if I had known beforehand how much work was needed. But since it is done now I think it is worth merging nevertheless. Some parts are still pure code cleanups anyway. Overall the larger projects are likely to benefit more as they have a larger proportion of deltas. On the historic Linux archive the pack reduction is about 5%. Nicolas ``` ## Junio C Hamano, 2006-09-21 05:30 Subject: Re: [PATCH 0/6] packed deltas with offset to base instead of sha1 Message-ID: <7v4pv1eqgl.fsf@assigned-by-dhcp.cox.net> URL: https://gitlist.dev/e/7v4pv1eqgl.fsf%40assigned-by-dhcp.cox.net In-Reply-To: ``` Nicolas Pitre writes: > The following patches are the result of my work to allow deltas to have > their base specified as an offset within a pack instead of a 20 byte > sha1. > > This turned to be somewhat more involved than I originally expected. > Given the relative pack reduction resulting from that, I might have > decided against doing this if I had known beforehand how much work was > needed. > > But since it is done now I think it is worth merging nevertheless. Some > parts are still pure code cleanups anyway. > > Overall the larger projects are likely to benefit more as they have a > larger proportion of deltas. On the historic Linux archive the pack > reduction is about 5%. Nice, although I suspect this would make it a bit more involved to merge a few outstanding stuff. Will take a look when I'm done looking at Linus's packed-ref stuff. ``` ## Shawn Pearce, 2006-09-21 16:02 Subject: Re: [PATCH 0/6] packed deltas with offset to base instead of sha1 Message-ID: <20060921160227.GC3934@spearce.org> URL: https://gitlist.dev/e/20060921160227.GC3934%40spearce.org In-Reply-To: <7v4pv1eqgl.fsf@assigned-by-dhcp.cox.net> ``` Junio C Hamano wrote: > Nicolas Pitre writes: > > > The following patches are the result of my work to allow deltas to have > > their base specified as an offset within a pack instead of a 20 byte > > sha1. > > > > This turned to be somewhat more involved than I originally expected. > > Given the relative pack reduction resulting from that, I might have > > decided against doing this if I had known beforehand how much work was > > needed. > > > > But since it is done now I think it is worth merging nevertheless. Some > > parts are still pure code cleanups anyway. > > > > Overall the larger projects are likely to benefit more as they have a > > larger proportion of deltas. On the historic Linux archive the pack > > reduction is about 5%. > > Nice, although I suspect this would make it a bit more involved > to merge a few outstanding stuff. If you are talking about my mmap window code merge in Nico's work first. Nico posted before me and did so with a working implementation that looks good (at first glance anyway, I didn't study it in detail). I have yet to finish merging my mmap code onto your verify delta before reuse (106d710b) commits. I've just been too busy with classes and research work to get around to it. However I have looked at the merge and I more or less need to rewrite a good chunk of it just to get it onto 106d7; rewriting it onto Nico's work here is probably going to be about the same amount of effort. I'd prefer to rewrite it only once, given how limited my time has suddenly become. -- Shawn. ``` ## Junio C Hamano, 2006-09-22 04:57 Subject: Re: [PATCH 0/6] packed deltas with offset to base instead of sha1 Message-ID: <7v64fg7b1q.fsf@assigned-by-dhcp.cox.net> URL: https://gitlist.dev/e/7v64fg7b1q.fsf%40assigned-by-dhcp.cox.net In-Reply-To: <20060921160227.GC3934@spearce.org> ``` Shawn Pearce writes: >> Nice, although I suspect this would make it a bit more involved >> to merge a few outstanding stuff. > > If you are talking about my mmap window code merge in Nico's > work first... > However I have looked at the merge and I more or less need to > rewrite a good chunk of it just to get it onto 106d7; rewriting it > onto Nico's work here is probably going to be about the same amount > of effort. I had the same impression, although without seeing your code. Will see to it to have delta-offset code in "next" soonish. Thanks. ```