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Hello,

I replace one drive in account ring.
As I understand it, the balance should go to zero.

# swift-ring-builder account.builder
account.builder, build version 37
32 partitions, 3.000000 replicas, 2 regions, 5 zones, 5 devices, 300.00 balance
The minimum number of hours before a partition can be reassigned is 1
Devices:    id  region  zone      ip address  port  replication ip  replication port      name weight partitions balance meta
            11       1     2    10.76.92.132  6002    10.76.92.132              6002      sdb1  50.00         32  300.00
            12       2     3    10.76.92.133  6002    10.76.92.133              6002      sdb1  50.00         10   25.00
            13       2     4    10.76.92.134  6002    10.76.92.134              6002      sdb1  50.00         11   37.50
            14       2     5    10.76.92.135  6002    10.76.92.135              6002      sdb1  50.00         11   37.50
            15       1     1    10.76.92.129  6002    10.76.92.129              6002  accounts 400.00         32  -50.00
# swift-ring-builder account.builder rebalance
Cowardly refusing to save rebalance as it did not change at least 1%.

Why am I refused?

And one more question, maybe these problems are related. 
Why almost dormant cluster so many I/O operations? 
And writes mainly account-server.