Jeff King <peff@xxxxxxxx> writes:
> The code in prepare_midx_pack() converts a numeric pack id (referenced
> inside the midx) into a "struct packed_git" pointer, caching the results
> in multi_pack_index->packs. That field holds NULL for "we have not
> looked it up yet" or a valid pointer to a packed_git. It probably needs
> to hold a third state: "we tried and failed".
Yeah, this was exactly why I asked "are we having repeated failures
in the same process", and I am happy with this direction.
> Something like this (large untested) patch:
>
> diff --git a/midx.c b/midx.c
> index 3d0015f782..354b1f886c 100644
> --- a/midx.c
> +++ b/midx.c
> @@ -405,7 +405,7 @@ void close_midx(struct multi_pack_index *m)
> munmap((unsigned char *)m->data, m->data_len);
>
> for (i = 0; i < m->num_packs; i++) {
> - if (m->packs[i])
> + if (m->packs[i] && m->packs[i] != (void *)(intptr_t)-1)
> m->packs[i]->multi_pack_index = 0;
> }
> FREE_AND_NULL(m->packs);
> @@ -458,6 +458,8 @@ int prepare_midx_pack(struct repository *r, struct multi_pack_index *m,
>
> pack_int_id = midx_for_pack(&m, pack_int_id);
>
> + if (m->packs[pack_int_id] == (void *)(intptr_t)-1)
> + return 1;
> if (m->packs[pack_int_id])
> return 0;
>
> @@ -482,8 +484,10 @@ int prepare_midx_pack(struct repository *r, struct multi_pack_index *m,
> strbuf_release(&pack_name);
> strbuf_release(&key);
>
> - if (!p)
> + if (!p) {
> + m->packs[pack_int_id] = (void *)(intptr_t)-1;
> return 1;
> + }
>
> p->multi_pack_index = 1;
> m->packs[pack_int_id] = p;
