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lines changed Original file line number Diff line number Diff line change 125125 Both scanning the index and inserting tuples require locating the bucket
126126 where a given tuple ought to be located. To do this, we need the bucket
127127 count, highmask, and lowmask from the metapage; however, it's undesirable
128- for performance reasons to have to have to lock and pin the metapage for
129- every such operation. Instead, we retain a cached copy of the metapage
130- in each backend's relcache entry. This will produce the correct bucket
131- mapping as long as the target bucket hasn't been split since the last
132- cache refresh.
128+ for performance reasons to have to lock and pin the metapage for every such
129+ operation. Instead, we retain a cached copy of the metapage in each
130+ backend's relcache entry. This will produce the correct bucket mapping as
131+ long as the target bucket hasn't been split since the last cache refresh.
133132 </para>
134133
135134 <para>
Original file line number Diff line number Diff line change @@ -171,11 +171,10 @@ Metapage Caching
171171Both scanning the index and inserting tuples require locating the bucket
172172where a given tuple ought to be located. To do this, we need the bucket
173173count, highmask, and lowmask from the metapage; however, it's undesirable
174- for performance reasons to have to have to lock and pin the metapage for
175- every such operation. Instead, we retain a cached copy of the metapage
176- in each backend's relcache entry. This will produce the correct
177- bucket mapping as long as the target bucket hasn't been split since the
178- last cache refresh.
174+ for performance reasons to have to lock and pin the metapage for every such
175+ operation. Instead, we retain a cached copy of the metapage in each backend's
176+ relcache entry. This will produce the correct bucket mapping as long as the
177+ target bucket hasn't been split since the last cache refresh.
179178
180179To guard against the possibility that such a split has occurred, the
181180primary page of each bucket chain stores the number of buckets that
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