[Windows]65% regression from 2.5.1 in Rebalance after failover with views and query workload.

Rebalance after failover time increased from 310.4 to 513 minutes from 2.5.1 to 3.0.1.

Test details:
Rebalance after failover (min), 3 -> 4, 1 bucket x 100M x 2KB, 1 x 1 views, 10K ops/sec, 400 queries/sec

Observations (2.5.1 vs 3.0.1):

15x increase in bg_fetch latency from 180us to 2750us.
23x decrease in avg disk update time from max of 70us to 3us.
4x increase in 90 percentile query latency from 14ms to 55ms.
cache miss rate under 2% in both runs.
active resident ratio ~30% in both runs.

machine details:
RAID 10 HDD
24 vCPU, 64 GB

links:
http://cbmonitor.sc.couchbase.com/reports/html/?snapshot=zeus_301-1330_749_rebalance
http://cbmonitor.sc.couchbase.com/reports/html/?snapshot=zeus_251-1083_40b_rebalance

logs:
http://ci.sc.couchbase.com/job/zeus-64/1217/artifact/172.23.96.25.zip
http://ci.sc.couchbase.com/job/zeus-64/1217/artifact/172.23.96.26.zip
http://ci.sc.couchbase.com/job/zeus-64/1217/artifact/172.23.96.27.zip
http://ci.sc.couchbase.com/job/zeus-64/1217/artifact/172.23.96.28.zip
http://ci.sc.couchbase.com/job/zeus-64/1217/artifact/master_events.zip