[backport 3.4] salad: reserve block before bps_tree_insert_first_elem#11886
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sergepetrenko merged 1 commit intorelease/3.4from Oct 9, 2025
Merged
[backport 3.4] salad: reserve block before bps_tree_insert_first_elem#11886sergepetrenko merged 1 commit intorelease/3.4from
sergepetrenko merged 1 commit intorelease/3.4from
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The commit 51c56d9 ("salad: reserve extents for matras_touch on BPS tree operations") already made the tree self-sufficient - reserved blocks in garbage and extents for `matras_touch` calls prior to insertion and deletion. However, it didn't account for the addition of the first element to the tree, which creates the root leaf - this could also trigger `matras_touch` in `bps_tree_garbage_pop`. However, it turns out there is no need to touch blocks before taking them out of the garbage. There is an invariant that blocks in the garbage are definitely not used by any read views. Although from the point of view of the matras, they require copying and could potentially have been needed by these read views. Let's just remove this `matras_touch` from `bps_tree_garbage_pop`. Also let's reserve a block in the garbage before calling `bps_tree_insert_first_elem` to bring the tree even closer to self-sufficiency. Closes #11788 NO_DOC=bugfix (cherry picked from commit 52b3d4b)
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(This PR is a backport of #11857 to
release/3.4to a future3.4.2release.)The commit 51c56d9 ("salad: reserve extents for matras_touch on BPS tree operations") already made the tree self-sufficient - reserved blocks in garbage and extents for
matras_touchcalls prior to insertion and deletion. However, it didn't account for the addition of the first element to the tree, which creates the root leaf - this could also triggermatras_touchinbps_tree_garbage_pop.However, it turns out there is no need to touch blocks before taking them out of the garbage. There is an invariant that blocks in the garbage are definitely not used by any read views. Although from the point of view of the matras, they require copying and could potentially have been needed by these read views. Let's just remove this
matras_touchfrombps_tree_garbage_pop. Also let's reserve a block in the garbage before callingbps_tree_insert_first_elemto bring the tree even closer to self-sufficiency.Closes #11788
NO_DOC=bugfix