Add rocksdb.iterator.internal-key property

Summary:
Added a new iterator property: `rocksdb.iterator.internal-key` to get the internal-key (converted to user key) at which the iterator stopped.
Closes https://github.com/facebook/rocksdb/pull/3525

Differential Revision: D7033694

Pulled By: sagar0

fbshipit-source-id: d51e6c00f5e9d766c6276ef79774b81c6c5216f8
This commit is contained in:
Sagar Vemuri 2018-02-20 19:05:21 -08:00 committed by Facebook Github Bot
parent e9c31ab159
commit 8ada876dfe
3 changed files with 55 additions and 0 deletions

View file

@ -217,6 +217,9 @@ class DBIter final: public Iterator {
*prop = "Iterator is not valid.";
}
return Status::OK();
} else if (prop_name == "rocksdb.iterator.internal-key") {
*prop = saved_key_.GetUserKey().ToString();
return Status::OK();
}
return Status::InvalidArgument("Undentified property.");
}

View file

@ -81,6 +81,7 @@ TEST_P(DBIteratorTest, IteratorProperty) {
Options options = CurrentOptions();
CreateAndReopenWithCF({"pikachu"}, options);
Put(1, "1", "2");
Delete(1, "2");
ReadOptions ropt;
ropt.pin_data = false;
{
@ -90,9 +91,15 @@ TEST_P(DBIteratorTest, IteratorProperty) {
ASSERT_NOK(iter->GetProperty("non_existing.value", &prop_value));
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("0", prop_value);
ASSERT_OK(iter->GetProperty("rocksdb.iterator.internal-key", &prop_value));
ASSERT_EQ("1", prop_value);
iter->Next();
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("Iterator is not valid.", prop_value);
// Get internal key at which the iteration stopped (tombstone in this case).
ASSERT_OK(iter->GetProperty("rocksdb.iterator.internal-key", &prop_value));
ASSERT_EQ("2", prop_value);
}
Close();
}
@ -2183,6 +2190,48 @@ TEST_P(DBIteratorTest, SkipStatistics) {
ASSERT_EQ(skip_count, TestGetTickerCount(options, NUMBER_ITER_SKIP));
}
TEST_P(DBIteratorTest, SeekAfterHittingManyInternalKeys) {
Options options = CurrentOptions();
DestroyAndReopen(options);
ReadOptions ropts;
ropts.max_skippable_internal_keys = 2;
Put("1", "val_1");
// Add more tombstones than max_skippable_internal_keys so that Next() fails.
Delete("2");
Delete("3");
Delete("4");
Delete("5");
Put("6", "val_6");
unique_ptr<Iterator> iter(NewIterator(ropts));
iter->SeekToFirst();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().ToString(), "1");
ASSERT_EQ(iter->value().ToString(), "val_1");
// This should fail as incomplete due to too many non-visible internal keys on
// the way to the next valid user key.
iter->Next();
ASSERT_TRUE(!iter->Valid());
ASSERT_TRUE(iter->status().IsIncomplete());
// Get the internal key at which Next() failed.
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.internal-key", &prop_value));
ASSERT_EQ("4", prop_value);
// Create a new iterator to seek to the internal key.
unique_ptr<Iterator> iter2(NewIterator(ropts));
iter2->Seek(prop_value);
ASSERT_TRUE(iter2->Valid());
ASSERT_OK(iter2->status());
ASSERT_EQ(iter2->key().ToString(), "6");
ASSERT_EQ(iter2->value().ToString(), "val_6");
}
INSTANTIATE_TEST_CASE_P(DBIteratorTestInstance, DBIteratorTest,
testing::Values(true, false));

View file

@ -97,6 +97,9 @@ class Iterator : public Cleanable {
// Property "rocksdb.iterator.super-version-number":
// LSM version used by the iterator. The same format as DB Property
// kCurrentSuperVersionNumber. See its comment for more information.
// Property "rocksdb.iterator.internal-key":
// Get the user-key portion of the internal key at which the iteration
// stopped.
virtual Status GetProperty(std::string prop_name, std::string* prop);
private: