While working on another issue (#16580), the list of uncleaned pubkeys
returned from `remove_uncleaned_slots_and_collect_pubkeys_up_to_slot()`
did not include unrooted slots. This meant that during cleaning,
unrooted slots would not have their pubkeys cleaned up properly.
Now, return all uncleaned pubkeys, regardless if the slot is rooted or
not. Additionally, update the tests to have unrooted slots to ensure
this behavior.
This is part two of PR #16879, and originally based on PR #15106.
* Refactor `collect_uncleaned_pubkeys_to_slot()`
While working on another issue (#16580), I came across
`collect_unclean_pubkeys_to_slot()` and had difficulty understanding it.
Since the function does a few logically separate things, I split the
function up. I also added documentation, removed an unused return value,
and renamed the functions to be more specific.
This commit is to split up an existing PR (#16786), where I had both this
aesthetic change _and_ a behavioral change.
It is crucial that VersionedCrdsValue::insert_timestamp does not go
backward in time:
https://github.com/solana-labs/solana/blob/ec37a843a/core/src/crds.rs#L67-L79
Otherwise methods such as get_votes and get_epoch_slots_since will
break, which will break their downstream flow, including vote-listener
and optimistic confirmation:
https://github.com/solana-labs/solana/blob/ec37a843a/core/src/cluster_info.rs#L1197-L1215https://github.com/solana-labs/solana/blob/ec37a843a/core/src/cluster_info.rs#L1274-L1298
For that, Crds::new_versioned is intended to be called "atomically" with
Crds::insert_verioned (as the comment already says so):
https://github.com/solana-labs/solana/blob/ec37a843a/core/src/crds.rs#L126-L129
However, currently this is violated in the code. For example,
filter_pull_responses creates VersionedCrdsValues (with the current
timestamp), then acquires an exclusive lock on gossip, then
process_pull_responses writes those values to the crds table:
https://github.com/solana-labs/solana/blob/ec37a843a/core/src/cluster_info.rs#L2375-L2392
Depending on the workload and lock contention, the insert_timestamps may
well be in the past when these values finally are inserted into gossip.
To avoid such scenarios, this commit:
* removes Crds::new_versioned and Crd::insert_versioned.
* makes VersionedCrdsValue constructor private, only invoked in
Crds::insert, so that insert_timestamp is populated right before
insert.
This will improve insert_timestamp monotonicity as long as Crds::insert
is not called with a stalled timestamp. Following commits may further
improve this by calling timestamp() inside Crds::insert, and/or
switching to std::time::Instant which guarantees monotonicity.
Strip the zero-padding off of data shreds before insertion into blockstore
Co-authored-by: Stephen Akridge <sakridge@gmail.com>
Co-authored-by: Nathan Hawkins <utsl@utsl.org>
