From 3964fc2aae7c7420a4c5da1b9530e8e8de1ed367 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Tue, 30 Mar 2021 13:10:47 +0000 Subject: sparse-index: add guard to ensure full index Upcoming changes will introduce modifications to the index format that allow sparse directories. It will be useful to have a mechanism for converting those sparse index files into full indexes by walking the tree at those sparse directories. Name this method ensure_full_index() as it will guarantee that the index is fully expanded. This method is not implemented yet, and instead we focus on the scaffolding to declare it and call it at the appropriate time. Add a 'command_requires_full_index' member to struct repo_settings. This will be an indicator that we need the index in full mode to do certain index operations. This starts as being true for every command, then we will set it to false as some commands integrate with sparse indexes. If 'command_requires_full_index' is true, then we will immediately expand a sparse index to a full one upon reading from disk. This suffices for now, but we will want to add more callers to ensure_full_index() later. Signed-off-by: Derrick Stolee Signed-off-by: Junio C Hamano --- repo-settings.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'repo-settings.c') diff --git a/repo-settings.c b/repo-settings.c index f7fff0f5ab..d63569e404 100644 --- a/repo-settings.c +++ b/repo-settings.c @@ -77,4 +77,12 @@ void prepare_repo_settings(struct repository *r) UPDATE_DEFAULT_BOOL(r->settings.core_untracked_cache, UNTRACKED_CACHE_KEEP); UPDATE_DEFAULT_BOOL(r->settings.fetch_negotiation_algorithm, FETCH_NEGOTIATION_DEFAULT); + + /* + * This setting guards all index reads to require a full index + * over a sparse index. After suitable guards are placed in the + * codebase around uses of the index, this setting will be + * removed. + */ + r->settings.command_requires_full_index = 1; } -- cgit 1.2.3-korg From 58300f4743231724686d9ddf481aeefa4f90d2f7 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Tue, 30 Mar 2021 13:10:59 +0000 Subject: sparse-index: add index.sparse config option When enabled, this config option signals that index writes should attempt to use sparse-directory entries. Signed-off-by: Derrick Stolee Signed-off-by: Junio C Hamano --- Documentation/config/index.txt | 5 +++++ cache.h | 1 + repo-settings.c | 7 +++++++ repository.h | 3 ++- sparse-index.c | 34 +++++++++++++++++++++++++++++----- 5 files changed, 44 insertions(+), 6 deletions(-) (limited to 'repo-settings.c') diff --git a/Documentation/config/index.txt b/Documentation/config/index.txt index 7cb50b37e9..75f3a2d105 100644 --- a/Documentation/config/index.txt +++ b/Documentation/config/index.txt @@ -14,6 +14,11 @@ index.recordOffsetTable:: Defaults to 'true' if index.threads has been explicitly enabled, 'false' otherwise. +index.sparse:: + When enabled, write the index using sparse-directory entries. This + has no effect unless `core.sparseCheckout` and + `core.sparseCheckoutCone` are both enabled. Defaults to 'false'. + index.threads:: Specifies the number of threads to spawn when loading the index. This is meant to reduce index load time on multiprocessor machines. diff --git a/cache.h b/cache.h index 74b43aaa2b..8aede373ae 100644 --- a/cache.h +++ b/cache.h @@ -1059,6 +1059,7 @@ struct repository_format { int worktree_config; int is_bare; int hash_algo; + int sparse_index; char *work_tree; struct string_list unknown_extensions; struct string_list v1_only_extensions; diff --git a/repo-settings.c b/repo-settings.c index d63569e404..0cfe8b787d 100644 --- a/repo-settings.c +++ b/repo-settings.c @@ -85,4 +85,11 @@ void prepare_repo_settings(struct repository *r) * removed. */ r->settings.command_requires_full_index = 1; + + /* + * Initialize this as off. + */ + r->settings.sparse_index = 0; + if (!repo_config_get_bool(r, "index.sparse", &value) && value) + r->settings.sparse_index = 1; } diff --git a/repository.h b/repository.h index e06a230156..a45f7520fd 100644 --- a/repository.h +++ b/repository.h @@ -42,7 +42,8 @@ struct repo_settings { int core_multi_pack_index; - unsigned command_requires_full_index:1; + unsigned command_requires_full_index:1, + sparse_index:1; }; struct repository { diff --git a/sparse-index.c b/sparse-index.c index 7631f7bd00..6f4d95d35b 100644 --- a/sparse-index.c +++ b/sparse-index.c @@ -102,19 +102,43 @@ static int convert_to_sparse_rec(struct index_state *istate, return num_converted - start_converted; } +static int enable_sparse_index(struct repository *repo) +{ + const char *config_path = repo_git_path(repo, "config.worktree"); + + git_config_set_in_file_gently(config_path, + "index.sparse", + "true"); + + prepare_repo_settings(repo); + repo->settings.sparse_index = 1; + return 0; +} + int convert_to_sparse(struct index_state *istate) { if (istate->split_index || istate->sparse_index || !core_apply_sparse_checkout || !core_sparse_checkout_cone) return 0; + if (!istate->repo) + istate->repo = the_repository; + + /* + * The GIT_TEST_SPARSE_INDEX environment variable triggers the + * index.sparse config variable to be on. + */ + if (git_env_bool("GIT_TEST_SPARSE_INDEX", 0)) { + int err = enable_sparse_index(istate->repo); + if (err < 0) + return err; + } + /* - * For now, only create a sparse index with the - * GIT_TEST_SPARSE_INDEX environment variable. We will relax - * this once we have a proper way to opt-in (and later still, - * opt-out). + * Only convert to sparse if index.sparse is set. */ - if (!git_env_bool("GIT_TEST_SPARSE_INDEX", 0)) + prepare_repo_settings(istate->repo); + if (!istate->repo->settings.sparse_index) return 0; if (!istate->sparse_checkout_patterns) { -- cgit 1.2.3-korg