refs/reftable: allow configuring geometric factor
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 <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt committed
May 13, 2024 at 10:18 UTC
f518d91a2b6465c9951f4ee1ab316ee81894000c
2 files changed
+15
Documentation/config/reftable.txt
+10
@@ -36,3 +36,13 @@ reftable.indexObjects::
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are a reverse mapping of object ID to the references pointing to them.
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+
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The default value is `true`.
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+
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+reftable.geometricFactor::
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+ Whenever the reftable backend appends a new table to the stack, it
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+ performs auto compaction to ensure that there is only a handful of
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+ tables. The backend does this by ensuring that tables form a geometric
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+ sequence regarding the respective sizes of each table.
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++
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+By default, the geometric sequence uses a factor of 2, meaning that for any
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+table, the next-biggest table must at least be twice as big. A maximum factor
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+of 256 is supported.
refs/reftable-backend.c
+5
@@ -247,6 +247,11 @@ static int reftable_be_config(const char *var, const char *value,
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opts->restart_interval = restart_interval;
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} else if (!strcmp(var, "reftable.indexobjects")) {
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opts->skip_index_objects = !git_config_bool(var, value);
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+ } else if (!strcmp(var, "reftable.geometricfactor")) {
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+ unsigned long factor = git_config_ulong(var, value, ctx->kvi);
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+ if (factor > UINT8_MAX)
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+ die("reftable geometric factor cannot exceed %u", (unsigned)UINT8_MAX);
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+ opts->auto_compaction_factor = factor;
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}
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return 0;