Restore the timestamp build flag. Some test code on the way.
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What a bug!!! We do not need to scan the specific block when calculating tupleID in LRU.
Replace set to sort in EvictionIterator.
Add the sort to EvictionIterator.
Replace the tuple-based sampling to block-based in anti-cache timestamps.
Add one block to evict to ensure there's someting when evict_num is really low.
Clean up the allocatortracker test.
Little change to #sample-block.
Rollback the block-sample to tuple-sample. Cleanup of codes.
Add more comments.
Commit the scripts for anti-cache timestamps.
Add index memory back when calculating eviction threshold.