From d58c3fd2c868c2b8eb562f00a2673458b6c0075c Mon Sep 17 00:00:00 2001 From: PedroHenrique0713 Date: Wed, 2 Sep 2026 18:35:59 -0300 Subject: [PATCH] docs: document the symbol capacity auto-scaling keys cairo.auto.scale.symbol.capacity and cairo.auto.scale.symbol.capacity.threshold govern the automatic symbol capacity described in concepts/symbol, but neither key was listed on the Cairo engine configuration page. Defaults and behaviour taken from the core: PropServerConfiguration reads the flag with a default of true and the threshold with a default of 0.8, rejecting a non-positive or non-finite threshold at startup. Neither key is in the dynamicProps set of DynamicPropServerConfiguration, so both need a restart. --- documentation/configuration/cairo-engine.md | 26 +++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/documentation/configuration/cairo-engine.md b/documentation/configuration/cairo-engine.md index e809a8adc..6b97b57d2 100644 --- a/documentation/configuration/cairo-engine.md +++ b/documentation/configuration/cairo-engine.md @@ -281,6 +281,32 @@ Estimated partition size on disk. This is one of the conditions that triggers ## Symbol and indexing +### cairo.auto.scale.symbol.capacity + +- **Default**: `true` +- **Reloadable**: no + +Enables symbol capacity auto-scaling, which resizes the symbol table data +structures as the number of symbols in a table grows. Keeping these structures +optimally sized is what makes +[symbol capacity automatic](/docs/concepts/symbol/) from QuestDB 9.0.0 onwards, +and it is the recommended setting. Disable it only to work around a problem +with auto-scaling itself. + +Changing this setting requires a database restart. + +### cairo.auto.scale.symbol.capacity.threshold + +- **Default**: `0.8` +- **Reloadable**: no + +Fraction of the symbol table capacity at which the table is resized. With the +default of `0.8`, the symbol table is resized as soon as the symbol count goes +over 80% of the current capacity. + +Must be a positive, non-zero, finite number. Any other value stops the server +from starting. + ### cairo.default.symbol.cache.flag - **Default**: `true`