Alexandru Vasile
287b116c3e
This PR ensure that the distance between any leaf and the finalized block is within a reasonable distance. For a new subscription, the chainHead has to provide all blocks between the leaves of the chain and the finalized block. When the distance between a leaf and the finalized block is large: - The tree route is costly to compute - We could deliver an unbounded number of blocks (potentially millions) (For more details see https://github.com/paritytech/polkadot-sdk/pull/3445#discussion_r1507210283) The configuration of the ChainHead is extended with: - suspend on lagging distance: When the distance between any leaf and the finalized block is greater than this number, the subscriptions are suspended for a given duration. - All active subscriptions are terminated with the `Stop` event, all blocks are unpinned and data discarded. - For incoming subscriptions, until the suspended period expires the subscriptions will immediately receive the `Stop` event. - Defaults to 128 blocks - suspended duration: The amount of time for which subscriptions are suspended - Defaults to 30 seconds cc @paritytech/subxt-team --------- Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io> Co-authored-by: Sebastian Kunert <skunert49@gmail.com>
Substrate
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