On Thu, Sep 27, 2012 at 10:51 PM, Shawn Pearce <spearce@xxxxxxxxxxx> wrote: > In Linus' Linux kernel tree there are currently about 323,178 commits. > If we store just the pre-parsed commit time as an int32 field this is > an additional 1.2 MiB of data in the pack-*.idx file, assuming we can > use additional data like pack offset position to correlate commit to > the parsed int. If we stored parent pointers in a similar way you > probably need at least 3.6 MiB of additional disk space on the index. > For example, use 12 bytes for each commit to store enough of the > parsed commit time to sort commits, and up to 2 parent pointers per > commit.... with a reserved magic value for octopus merges to mean the > commit itself has to be parsed to get the graph structure correct. This is much better than my naive approach (storing sha-1 and timestamps). We could use less space by storing parent pointer of non-merge commits only. Merge commits linux-2.6 is 6% the number of commits. git.git has higher percentage, 21%. I bet many projects do not merge as much and the number of merge commits is less than 5%. -- Duy -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html