Reclaim PagesSerde memory in Query #15270
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findepi
approved these changes
Dec 1, 2022
| @@ -575,6 +577,7 @@ private synchronized QueryResultRows removePagesFromExchange(QueryInfo queryInfo | |||
| } | |||
| if (exchangeDataSource.isFinished()) { | |||
| exchangeDataSource.close(); | |||
| serde = null; // null to reclaim memory | |||
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is it worth adding code comment why serde is more to null out important than eg exchangeDataSource?
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I think ideally it would be great to account for PageSerde memory in operators. A single PageSerde can retain up to 128KB of memory (when both encryption and compression are enabled). Hard to say how many open Exchange/TaskOutput operators can be open at the same time, but in theory it can accumulate.
Created an issue: #15273
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I made comment more descriptive
arhimondr
approved these changes
Dec 1, 2022
|
Great catch. Let's get this in before the release |
When we finish reading data for a query we can safely null reference to PagesSerde used for deserializing query results. This allow GCing buffer references stored in PagesSerde.
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When we finish reading data for a query we can
safely null reference to PagesSerde used for deserializing query results. This allow GCing buffer references stored in PagesSerde.
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