Delay Presto map hash table build when lookups are few #22587
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elharo
requested changes
Apr 22, 2024
| return 2 * i + 1; | ||
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| catch (Throwable throwable) { |
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Per Effective Java, you should almost never catch Throwable. What's the more specific exception here?
| return 2 * i + 1; | ||
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| catch (Throwable throwable) { |
| return 2 * i + 1; | ||
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| catch (Throwable throwable) { |
| return 2 * i + 1; | ||
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| } | ||
| catch (Throwable throwable) { |
| return 2 * i + 1; | ||
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| } | ||
| catch (Throwable throwable) { |
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@pranjalssh, @mbasmanova : Is there an equivalent for this in Prestissimo engine ? My intuition is that because of runtime optimizations in HashTable build we might not need this. But just thought to ask anyways. |
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Add session property
map_lookups_without_hashtable, which denotes how many map lookups will be done using linear search, before resorting to hash table build of the entire map. Default is 0.Usually hashing cost is high enough that its best to not build the hash table for map objects. Only when number of lookups exceed some threshold, we should resort to build the hashtable. This change controls that using a session prop.