[ntuple] Memory optimization for the descriptor - #23400
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Test Results 23 files 23 suites 3d 16h 57m 15s ⏱️ For more details on these failures, see this check. Results for commit a3d6a1b. ♻️ This comment has been updated with latest results. |
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Thanks. looks good to me, just a couple more comments
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Reduce size of the struct from 72 to 56 bytes (in most cases, unless the column has a value range)
This factory method is an unnecessary complication. Field descriptors are now directly added from RFieldBase objects through a new RNTupleDescriptorBuilder::AddField() overload.
Member reordering reduced the size from 248B to 240B.
...instead of cloning it. Avoids the memory copies.
...instead of cloning it. Avoids the memory copies.
...instead of cloning.
An internal utility class that maintains a sorted list of immutable strings.
Let the field descriptors strings be stored in the string pool of the surrounding RNTupleDescriptor. Deduplicates the type names and field names. Also reduces the size of the RFieldDescriptor struct from 240B to 152B.
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Several optimizations to reduce the memory footprint and the number of memory copies of the schema part of the descriptor. Most notably introduces string interning for the field descriptor strings.