I/O recommendations for optimizing performance

If you are testing the Dgraph maximum throughput using Eneperf with an adequate num connections and the CPU is still not fully utilized, I/O could be a problem, especially if your application is search intensive but light on other features.

There is no absolute threshold that indicates that an application is I/O bound, but typical symptoms include very high numbers of I/O hits per second or KB per second. If I/O is below the specifications for the hardware, it is less likely to be a problem. In some cases, it is even possible to go beyond a device’s theoretical maximum because of disk caching.

To determine the level of I/O activity, use the following tools:

On Solaris, run iostat -2
On Linux, run sar -b
On Windows, do the following:
On the Task Manager, open the Processes tab.

From the menus, select View > Select Columns.

Check I/O Reads, I/O Read Bytes, I/O Writes, and I/O Write Bytes. These options enable new columns in the Processes pane that provide similar information to sar -b on UNIX.