To see how much sequential write your hard disk can handle, run

dd if=/dev/zero of=hon-test bs=64k count=16k conv=fdatasync && rm -f hon-test

Example

[root@ssd backup]# dd if=/dev/zero of=hon-test bs=64k count=16k conv=fdatasync && rm -f hon-test 
16384+0 records in
16384+0 records out
1073741824 bytes (1.1 GB) copied, 6.86452 s, 156 MB/s
[root@ssd backup]# 

This is not actual real world write speed, but give an idea how much write speed you can get on a disk.