Summary:
This diff improves the memory utilization for tailing iterators RocksDB,
by freeing file iterators which are over the upper bound.
It is an updating on Siying's original diff for improving the memory usage for
tailing iterators. The changes for the seek and next path are now complete
and a test has been added to exercise these paths while deleting file iterators
which are above the upper bound.
Test Plan: db_tailing_iter_test.TailingIteratorTrimSeekToNext
Reviewers: march, tnovak, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D43833
Summary:
Reseek mutable_iter if it is invalid in Next and immutable_iter
is invalid.
Test Plan: DBTestTailingIterator.TailingIteratorSeekToNext
Reviewers: tnovak, march, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D44865
Venkatesh Radhakrishnan