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If the I/O load on the operating node is too large and the maximum I/O duration occurs over a long period of time (several minutes to several tens of minutes), DRX buffering can be difficult to handle. In this case, you should consider data compression.
2.3.1 Congestion policy
The congestion state means that buffering is impossible because there is no free space in the DRX buffer because the replication load is increased. In this case, DRX does not perform any special action and concentrates on remotely transmitting the replicated data in the buffer. The response to the congestion state is left to the congestion policy of DRBD.
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