database::drop_column_family(): has a window where new queries can be created for the dropped cf #10450
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denesb
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avikivity
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… querier cache entries' from Botond Dénes Said method has to evict all querier cache entries, belonging to the to-be-dropped table. This is already the case, but there was a window where new entries could sneak in, causing a stale reference to the table to be de-referenced later when they are evicted due to TTL. This window is now closed, the entries are evicted after the method has waited for all ongoing operations on said table to stop. Fixes: #10450 Closes #10451 * github.com:scylladb/scylla: replica/database: drop_column_family(): drop querier cache entries after waiting for ops replica/database: finish coroutinizing drop_column_family() replica/database: make remove(const column_family&) private (cherry picked from commit 7f1e368)
avikivity
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… querier cache entries' from Botond Dénes Said method has to evict all querier cache entries, belonging to the to-be-dropped table. This is already the case, but there was a window where new entries could sneak in, causing a stale reference to the table to be de-referenced later when they are evicted due to TTL. This window is now closed, the entries are evicted after the method has waited for all ongoing operations on said table to stop. Fixes: #10450 Closes #10451 * github.com:scylladb/scylla: replica/database: drop_column_family(): drop querier cache entries after waiting for ops replica/database: finish coroutinizing drop_column_family() replica/database: make remove(const column_family&) private (cherry picked from commit 7f1e368)
avikivity
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May 1, 2022
… querier cache entries' from Botond Dénes Said method has to evict all querier cache entries, belonging to the to-be-dropped table. This is already the case, but there was a window where new entries could sneak in, causing a stale reference to the table to be de-referenced later when they are evicted due to TTL. This window is now closed, the entries are evicted after the method has waited for all ongoing operations on said table to stop. Fixes: #10450 Closes #10451 * github.com:scylladb/scylla: replica/database: drop_column_family(): drop querier cache entries after waiting for ops replica/database: finish coroutinizing drop_column_family() replica/database: make remove(const column_family&) private (cherry picked from commit 7f1e368)
avikivity
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May 1, 2022
… querier cache entries' from Botond Dénes Said method has to evict all querier cache entries, belonging to the to-be-dropped table. This is already the case, but there was a window where new entries could sneak in, causing a stale reference to the table to be de-referenced later when they are evicted due to TTL. This window is now closed, the entries are evicted after the method has waited for all ongoing operations on said table to stop. Fixes: #10450 Closes #10451 * github.com:scylladb/scylla: replica/database: drop_column_family(): drop querier cache entries after waiting for ops replica/database: finish coroutinizing drop_column_family() replica/database: make remove(const column_family&) private (cherry picked from commit 7f1e368)
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Backported to 4.5, 4.6, 5.0. |
avikivity
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May 1, 2022
… querier cache entries' from Botond Dénes Said method has to evict all querier cache entries, belonging to the to-be-dropped table. This is already the case, but there was a window where new entries could sneak in, causing a stale reference to the table to be de-referenced later when they are evicted due to TTL. This window is now closed, the entries are evicted after the method has waited for all ongoing operations on said table to stop. Fixes: #10450 Closes #10451 * github.com:scylladb/scylla: replica/database: drop_column_family(): drop querier cache entries after waiting for ops replica/database: finish coroutinizing drop_column_family() replica/database: make remove(const column_family&) private (cherry picked from commit 7f1e368)
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When such an entry expire, it will cause a crash because destroying the reader objects requires the table object to be around (which obviously isn't after the drop).
https://github.com/scylladb/scylla/blob/333fdcb3f544a6fc2ef3066e2ddbf1bde18cb7a1/replica/database.cc#L930-L936
Even though all querier cache entries related to the to-be-dropped table are removed by
database::remove(), a read running concurrent todatabase::drop_column_family()can create a new querier, when said method yields to wait for ongoing operations.The text was updated successfully, but these errors were encountered: