Bank epoch schedule is not coupled to the epoch schedule sysvar

[jstarry]

Problem

Unlike other sysvars, the epoch schedule sysvar account is only ever updated during genesis. This is probably fine most of the time since the epoch schedule currently can't be changed. However, it seems that devnet was started with epochs that were only 8,192 slots long (reflected here: https://explorer.solana.com/address/SysvarEpochSchedu1e111111111111111111111111?cluster=devnet) which doesn't match the bank epoch schedule which states that epochs are the typical 432k slots long.

This means that devnet programs cannot get accurate epoch schedule data through the epoch schedule sysvar. Also, if the epoch schedule ever changes in the future (like perhaps the leader_schedule_slot_offset), those changes wouldn't be reflected in the sysvar.

Proposed Solution

Update the epoch schedule sysvar at the beginning of each epoch

[github-actions]

This repository is no longer in use. Please re-open this issue in the agave repo: https://github.com/anza-xyz/agave