#4384 added support for using CommitInBatch with delete requests which showed a very nice performance improvement for the Delete{1,10} benchmarks. But it resulted in a reproducible slowdown for the Delete100 benchmark. The code in question is in `sql/delete.go:

        pErr = p.txn.CommitInBatch(b)

The slowdown can removed by replacing this with: (this was what the code was doing before #4384).

        pErr = p.txn.Run(b)
        if pErr == nil {
            pErr = p.txn.Commit()
        }