On Fri, Aug 11, 2023 at 02:46:51PM -0700, Jonathan Tan wrote: > Taylor Blau <me@xxxxxxxxxxxx> writes: > > In subsequent commits, we will want to load existing Bloom filters out > > of a commit-graph, even when the hash version they were computed with > > does not match the value of `commitGraph.changedPathVersion`. > > > > In order to differentiate between the two, add a "filter" field to each > > Bloom filter. > > You mean "version", I think. Oops, yes -- I'm not sure how my editor tab-completed "version" there, but oh, well :-). > > @@ -55,6 +55,7 @@ struct bloom_filter_settings { > > struct bloom_filter { > > unsigned char *data; > > size_t len; > > + int version; > > }; > > We might want to shrink the sizes of len (we have a changed path limit > so we know exactly how big Bloom filters can get) and version so that > this struct doesn't take up more space. But if other reviewers think > that this is OK, I'm fine with that. I think that making len a size_t here is an appropriate choice. Even though the maximum length of a Bloom filter is well below the 2^64-1 threshold, we are often looking at a memory-mapped region here, so keeping track of it with a size_t / off_t seems reasonable to me. > Another thing that we might want to track is whether the Bloom filter is > a reference to an existing buffer (and thus does not need to be freed) > or a reference to a malloc-ed buffer that we must free. But both before > and after this patch set, a malloc-ed buffer is never overridden by a > reference-to-existing-buffer, so we should still be fine for now. (This > patch set does add a scenario in which a reference-to-existing buffer is > overridden by a malloc-ed buffer, but that's the only new scenario.) Yeah, I think there is some opportunity for clean-up here. I'll take a look... Thanks, Taylor