From: Patrick Steinhardt Date: Thu, 02 May 2024 06:52:23 GMT Subject: [PATCH 11/11] refs/reftable: allow configuring geometric factor Message-ID: <861f2e72d987d17b00d68cdaf400d743e2f8c118.1714630191.git.ps@pks.im> In-Reply-To: Allow configuring the geometric factor used by the auto-compaction algorithm whenever a new table is appended to the stack of tables. Signed-off-by: Patrick Steinhardt --- Documentation/config/reftable.txt | 10 ++++++++++ refs/reftable-backend.c | 5 +++++ 2 files changed, 15 insertions(+) diff --git a/Documentation/config/reftable.txt b/Documentation/config/reftable.txt index 6e4466f3c5..1c381dda04 100644 --- a/Documentation/config/reftable.txt +++ b/Documentation/config/reftable.txt @@ -37,3 +37,13 @@ reftable.indexObjects:: are a reverse mapping of object ID to the references pointing to them. + The default value is `true`. + +reftable.geometricFactor:: + Whenever the reftable backend appends a new table to the table it + performs auto compaction to ensure that there is only a handful of + tables. The backend does this by ensuring that tables form a geometric + sequence regarding the respective sizes of each table. ++ +By default, the geometric sequence uses a factor of 2, meaning that for any +table, the next-biggest table must at least be twice as big. A maximum factor +of 256 is supported. diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c index 5298fcef6e..657d227c12 100644 --- a/refs/reftable-backend.c +++ b/refs/reftable-backend.c @@ -252,6 +252,11 @@ static int reftable_be_config(const char *var, const char *value, } else if (!strcmp(var, "reftable.indexobjects")) { opts->skip_index_objects = !git_config_bool(var, value); return 0; + } else if (!strcmp(var, "reftable.geometricfactor")) { + unsigned long factor = git_config_ulong(var, value, ctx->kvi); + if (factor > UINT8_MAX) + die("reftable geometric factor cannot exceed %u", (unsigned)UINT8_MAX); + opts->auto_compaction_factor = factor; } return 0; -- 2.45.0