Getting FDB_RESULT_FAIL_BY_ROLLBACK

seeing FDB_RESULT_FAIL_BY_ROLLBACK in system test during key insertion

Logs are under /root/john-fdb-11 @172.23.105.60

goroutine 776 [running]:
panic(0xead380, 0xc8d7dafbc8)
/home/couchbase/.cbdepscache/exploded/x86_64/go-1.6/go/src/runtime/panic.go:464 +0x3e6 fp=0xca68d15a50 sp=0xca68d159d0
github.com/couchbase/indexing/secondary/common.CrashOnError(0x7f6c781b1928, 0xc8d7dafbc8)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/common/util.go:368 +0x4b fp=0xca68d15a78 sp=0xca68d15a50
github.com/couchbase/indexing/secondary/indexer.(*fdbSlice).checkFatalDbError(0xc8220fdb80, 0x7f6c781b1928, 0xc8d7dafbc8)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/forestdb_slice_writer.go:823 +0x2f fp=0xca68d15ac8 sp=0xca68d15a78
github.com/couchbase/indexing/secondary/indexer.(*fdbSlice).insertSecIndex(0xc8220fdb80, 0xc97deae7e0, 0x21, 0x30, 0xc9ff32d940, 0x12, 0x12, 0x0, 0x0)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/forestdb_slice_writer.go:454 +0x121b fp=0xca68d15cd0 sp=0xca68d15ac8
github.com/couchbase/indexing/secondary/indexer.(*fdbSlice).insert(0xc8220fdb80, 0xc97deae7e0, 0x21, 0x30, 0xc9afe4ebd0, 0xd, 0x10, 0xc9ff32d940, 0x12, 0x12, ...)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/forestdb_slice_writer.go:353 +0xeb fp=0xca68d15d40 sp=0xca68d15cd0
github.com/couchbase/indexing/secondary/indexer.(*fdbSlice).handleCommandsWorker(0xc8220fdb80, 0x0)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/forestdb_slice_writer.go:314 +0x4c6 fp=0xca68d15f90 sp=0xca68d15d40
runtime.goexit()
/home/couchbase/.cbdepscache/exploded/x86_64/go-1.6/go/src/runtime/asm_amd64.s:1998 +0x1 fp=0xca68d15f98 sp=0xca68d15f90
created by github.com/couchbase/indexing/secondary/indexer.NewForestDBSlice
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/forestdb_slice_writer.go:158 +0x1990

goroutine 802 [runnable, locked to thread]:
runtime.cgocall(0xc897e0, 0xc8276b1820, 0x0)
/home/couchbase/.cbdepscache/exploded/x86_64/go-1.6/go/src/runtime/cgocall.go:123 +0x11b fp=0xc8276b17d0 sp=0xc8276b17a0
github.com/couchbase/indexing/secondary/fdb._Cfunc_fdb_rollback(0xc825bcd6c8, 0x0, 0xc900000000)
??:0 +0x41 fp=0xc8276b1820 sp=0xc8276b17d0
github.com/couchbase/indexing/secondary/fdb.(*KVStore).Rollback(0xc825bcd6b0, 0x0, 0x0, 0x0)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/fdb/commit.go:56 +0x312 fp=0xc8276b18b8 sp=0xc8276b1820
github.com/couchbase/indexing/secondary/indexer.(*fdbSlice).RollbackToZero(0xc8220fdb80, 0x0, 0x0)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/forestdb_slice_writer.go:953 +0x61 fp=0xc8276b1970 sp=0xc8276b18b8
github.com/couchbase/indexing/secondary/indexer.(*storageMgr).handleRollback(0xc824d55800, 0x7f6c7420c520, 0xc994553ea0)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/storage_manager.go:521 +0xc30 fp=0xc8276b1f10 sp=0xc8276b1970
github.com/couchbase/indexing/secondary/indexer.(*storageMgr).handleSupvervisorCommands(0xc824d55800, 0x7f6c7420c520, 0xc994553ea0)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/storage_manager.go:170 +0xda fp=0xc8276b1f30 sp=0xc8276b1f10
github.com/couchbase/indexing/secondary/indexer.(*storageMgr).run(0xc824d55800)
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/storage_manager.go:152 +0x184 fp=0xc8276b1f88 sp=0xc8276b1f30
runtime.goexit()
/home/couchbase/.cbdepscache/exploded/x86_64/go-1.6/go/src/runtime/asm_amd64.s:1998 +0x1 fp=0xc8276b1f90 sp=0xc8276b1f88
created by github.com/couchbase/indexing/secondary/indexer.NewStorageManager
/home/couchbase/jenkins/workspace/watson-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/storage_manager.go:129 +0x5a9