ydb-platform / nbs

Network Block & File Store
Apache License 2.0
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[Blockstore] 2/3 reading for mirror-3 disk #2077

Open sharpeye opened 2 months ago

sharpeye commented 2 months ago

In addition to the regular reading operation, mirror-3 disk could read a checksum from another replica, compare cehcksums and, if the comparition fails, perform a resync.

qkrorlqr commented 6 days ago

if the comparition fails, perform a resync.

this part will make the code more complex I decided to simply return E_REJECTED if the data is the same in 2 out of 3 replicas, one of the next retry attempts will hit those 2 replicas and succeed there's no point optimizing this scenario since it should never happen (or almost never) the discrepancy will be eventually fixed by the scrubbing process