eth/downloader, eth/sync: reduce sync stall on BSC's 0.45s block inte… #3556
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Contributor
|
maybe can solve this issue by adjust https://github.com/bnb-chain/bsc/blob/master/eth/downloader/downloader.go#L61 ？ |
flywukong
reviewed
Feb 10, 2026
| // If the node is only slightly behind (e.g., 1 block), syncing is unnecessary. | ||
| // It's likely still processing broadcasted blocks(such as including a big tx) or block hash announcements. | ||
| // In most cases, the node will catch up within 2 seconds. | ||
| time.Sleep(2 * time.Second) |
Contributor
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can we just change it to time.Sleep(500 * time.Millisecond)
allformless
reviewed
Feb 10, 2026
| case <-waitTimer.C: | ||
| case <-cs.handler.quitSync: | ||
| return nil | ||
| case <-cs.peerEventCh: |
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don't need trigger by this signal peerEventCh
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Description
Reduce sync stalls on BSC after the block interval was 0.45s. For #3525 #3548
Cap critical-path header timeout – Introduce masterPeerHeaderTimeout (5s) to bound blocking fetchHeadersByHash / fetchHeadersByNumber. The dynamic TargetTimeout can exceed 10s, stalling the entire pipeline on one slow peer. Also add missing cancelCh handling in fetchHeadersByHash.
Preserve forced sync on failure – Keep cs.forced = true on doSync error, so the sync loop retries immediately with minPeers=1 instead of waiting up to 10s.
Shorten near-head wait – Replace blocking 2s time.Sleep with a non-blocking 500ms select in nextSyncOp, responsive to quit signals and peer events.
Rationale
With 0.45s block intervals, the old parameters (designed for 3s/12s cadence) cause compounding delays: a single slow peer triggers a 10s+ timeout, followed by a 10s recovery wait — ~45 blocks of drift total. These changes reduce worst-case sync stall from ~20s to ~5s.
Changes