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Fix out-of-date version reference, grammar.
Time appears to be passing fast. Reported-By: Peter Geoghegan <pg@bowt.ie>
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@ -412,7 +412,7 @@ the cost of walking down the tree in such common cases.
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The optimization works on the assumption that there can only be one
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The optimization works on the assumption that there can only be one
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non-ignorable leaf rightmost page, and so not even a visible-to-everyone
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non-ignorable leaf rightmost page, and so not even a visible-to-everyone
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style interlock required. We cannot fail to detect that our hint was
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style interlock is required. We cannot fail to detect that our hint was
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invalidated, because there can only be one such page in the B-Tree at
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invalidated, because there can only be one such page in the B-Tree at
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any time. It's possible that the page will be deleted and recycled
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any time. It's possible that the page will be deleted and recycled
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without a backend's cached page also being detected as invalidated, but
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without a backend's cached page also being detected as invalidated, but
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@ -318,7 +318,7 @@ XID less than this could be about to appear in the ProcArray, because of the
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XidGenLock interlock discussed above.)
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XidGenLock interlock discussed above.)
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As GetSnapshotData is performance critical, it does not perform an accurate
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As GetSnapshotData is performance critical, it does not perform an accurate
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oldest-xmin calculation (it used to, until v13). The contents of a snapshot
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oldest-xmin calculation (it used to, until v14). The contents of a snapshot
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only depend on the xids of other backends, not their xmin. As backend's xmin
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only depend on the xids of other backends, not their xmin. As backend's xmin
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changes much more often than its xid, having GetSnapshotData look at xmins
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changes much more often than its xid, having GetSnapshotData look at xmins
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can lead to a lot of unnecessary cacheline ping-pong. Instead
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can lead to a lot of unnecessary cacheline ping-pong. Instead
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