Benchmarking Disks Reading and Writing Capacity
We already know how to measure the speed of our Ethernet through this article I wrote using iperf. Now let’s measure the speed of our records, very useful to identify eventual Bacula backup bottlenecks.
A nice software to do that is hdparm.
sudo hdparm -Tt /dev/sda /dev/sda: Timing cached reads: 12960 MB in 2.00 seconds = 6484.97 MB/sec Timing buffered disk reads: 398 MB in 3.00 seconds = 132.56 MB/sec
The values for each execution may suffer a small variance for each execution, but serve as a good parameter to know the ability to verify machines with Bacula Clients.
In this case we will use the old dd.
dd if=/dev/zero of=/tmp/output bs=8k count=250k; rm -f /tmp/output 256000+0 records in 256000+0 records out 2097152000 bytes (2,1 GB) copied, 16,5959 s, 126 MB/s
I chose 250k granularity to have significant total data for the test (2.1 GB) , but a larger test size may be more accurate and compatible with your actual workload .
If you do not have a file system still on disk, you can run the test as follows:
dd if=/dev/zero of=/tmp/output bs=8k count=10k; rm -f /tmp/output