fix: add sort_pushdown_buffer_capacity to information_schema SLT

Author: zhuqi-lucas

datafusion/sqllogictest/test_files/information_schema.slt

@@ -270,6 +270,7 @@ datafusion.execution.skip_partial_aggregation_probe_rows_threshold 100000
 datafusion.execution.skip_physical_aggregate_schema_check false
 datafusion.execution.soft_max_rows_per_output_file 50000000
 datafusion.execution.sort_in_place_threshold_bytes 1048576
+datafusion.execution.sort_pushdown_buffer_capacity 1073741824
 datafusion.execution.sort_spill_reservation_bytes 10485760
 datafusion.execution.spill_compression uncompressed
 datafusion.execution.split_file_groups_by_statistics false
@@ -413,6 +414,7 @@ datafusion.execution.skip_partial_aggregation_probe_rows_threshold 100000 Number
 datafusion.execution.skip_physical_aggregate_schema_check false When set to true, skips verifying that the schema produced by planning the input of `LogicalPlan::Aggregate` exactly matches the schema of the input plan. When set to false, if the schema does not match exactly (including nullability and metadata), a planning error will be raised. This is used to workaround bugs in the planner that are now caught by the new schema verification step.
 datafusion.execution.soft_max_rows_per_output_file 50000000 Target number of rows in output files when writing multiple. This is a soft max, so it can be exceeded slightly. There also will be one file smaller than the limit if the total number of rows written is not roughly divisible by the soft max
 datafusion.execution.sort_in_place_threshold_bytes 1048576 When sorting, below what size should data be concatenated and sorted in a single RecordBatch rather than sorted in batches and merged.
+datafusion.execution.sort_pushdown_buffer_capacity 1073741824 Maximum buffer capacity (in bytes) per partition for BufferExec inserted during sort pushdown optimization. When PushdownSort eliminates a SortExec under SortPreservingMergeExec, a BufferExec is inserted to replace SortExec's buffering role. This prevents I/O stalls by allowing the scan to run ahead of the merge. This uses strictly less memory than the SortExec it replaces (which buffers the entire partition). The buffer respects the global memory pool limit. Setting this to a large value is safe — actual memory usage is bounded by partition size and global memory limits.
 datafusion.execution.sort_spill_reservation_bytes 10485760 Specifies the reserved memory for each spillable sort operation to facilitate an in-memory merge. When a sort operation spills to disk, the in-memory data must be sorted and merged before being written to a file. This setting reserves a specific amount of memory for that in-memory sort/merge process. Note: This setting is irrelevant if the sort operation cannot spill (i.e., if there's no `DiskManager` configured).
 datafusion.execution.spill_compression uncompressed Sets the compression codec used when spilling data to disk. Since datafusion writes spill files using the Arrow IPC Stream format, only codecs supported by the Arrow IPC Stream Writer are allowed. Valid values are: uncompressed, lz4_frame, zstd. Note: lz4_frame offers faster (de)compression, but typically results in larger spill files. In contrast, zstd achieves higher compression ratios at the cost of slower (de)compression speed.
 datafusion.execution.split_file_groups_by_statistics false Attempt to eliminate sorts by packing & sorting files with non-overlapping statistics into the same file groups. Currently experimental