[RFC/PATCH 0/2] Speed up fetch with large number of tags

I have a repository at $dayjob where fetch was taking ~30s to tell me that there were no updates.

It turns out that I appear to have added a nasty linear search of all remote refs for every commit (i.e. tag^{}) tag ref way back in the original C implementation of fetch. This doesn't scale well to large numbers of refs, so this replaces it with a hash table based lookup instead, which brings the time down to a few seconds even for very large ref counts.

I haven't tested it with non-native transports, but there is no reason to believe that the code should be transport specific.

Julian Phillips (2):
  ref-dict: Add a set of functions for working with a ref dictionary
  fetch: Speed up fetch by using ref dictionary

 Makefile        |    1 +
 builtin-fetch.c |   19 ++++++-------
 ref-dict.c      |   76 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 ref-dict.h      |   13 +++++++++
 4 files changed, 99 insertions(+), 10 deletions(-)
 create mode 100644 ref-dict.c
 create mode 100644 ref-dict.h