Clean up and fix PER stats

[HaoranYi]

Problem

Now we enabled PER and deleted the old ER code path. There are a few stats that are missing from the PER code path.

load_vote_and_stake_accounts_us, hash reward partition timing and vote_accounts_cache_miss_count stats are not hooked up in PER code path.

Summary of Changes

• Remove stale PER stat - load_vote_and_stake_accounts_us (no longer applicable)
• fix hash reward partition timing stat
• add back vote_accounts_cache_miss_count

Fixes #

[t-nelson]

are there equivalents to some of these in another datapoint?

[HaoranYi]

are there equivalents to some of these in another datapoint?

load_vote_and_stake_accounts_us, vote_accounts_cache_miss_count are the stats
for old reward code before PER. These logics has been removed.

hash_partition_rewards_us was not poulated. Now this is fixed.

[brooksprumo]

Adding back in the hash_partition_rewards_us looks good to me.

For load_vote_and_stake_accounts_us and vote_accounts_cache_miss_count, can those be re-added too?

Looks like the get_vote_account lambda in calculate_stake_vote_rewards() could track the vote accounts cache misses.

I see that we get the stake accounts from the stakes cache, so that part is effectively 0. It looks like we could grab the vote account loading time though.

[HaoranYi]

vote_accounts_cache_miss_count should always be zero. That stat was added originally to assert that we cache all the vote accounts. It is mainly used to debug, not a meaningful stat for performance. but i can add it back along with the vote/stake account loading time.

[brooksprumo]

vote_accounts_cache_miss_count should always be zero. That stat was added originally to assert that we cache all the vote accounts.

Yeah, that's what I gathered from the code too. Should we assert the vote accounts are in the cache now, and not allow a fallback to loading from accounts-db?

And for this PR, if we do want to assert the vote accounts are in the cache, then I agree it makes sense to remove these two metrics (load_vote_and_stake_accounts_us and vote_accounts_cache_miss_count).

[HaoranYi]

I pushed a commit to add back vote_accounts_cache_miss_count in this PR. We could change it into an assert and get rid of the stat and account's db load fallback in a future PR.

I think load_vote_and_stake_accounts_us is no longer applicable. We load them from the cache. And that timing is already covered in measure_stake_rewards_us. So I keep it deleted.

[brooksprumo]

[t-nelson]

hash_partition_rewards_us was not poulated. Now this is fixed.

ah ok, this is the one i was looking for