# Local Disk I/O Performance Test

**Note: This document only provides benchmark values for IO performance. Since local disks are shared disks, their IO performance may fluctuate, resulting in performance that does not meet the levels tested in this document. If you require more stable IO, it is recommended that you choose cloud disks.**

## Disk Performance Indicators

**Sequential Read/Write** (Throughput, commonly measured in MB/s): Data is stored consecutively on the disk.

Applicable scenario: Large file copying (e.g., videos, music). Even high speeds have no reference value for database performance.

**4K Random Read/Write** (IOPS, common unit is times): Data is read/written at random positions on the disk, with each operation being 4KB.

Applicable scenarios: Operating system performance, software execution, and database operations.

The following are IO benchmark test data for the UHost Standard Edition and UHost High-Performance SSD Edition instance types. The tests were conducted using the universal I/O testing tool fio under the conditions of specified block sizes ("4K, 512K") and a queue depth of "128".

## Test Results

### Test 1. Sequential Read/Write 512K

![img](https://cdn.udelivrs.com/2025/04/76871367db868ee690e42ca5e033cbf2_1744194422933.jpg)<br>

(Comparison between local normal disk and local SSD)

### Test 2. Random Read/Write 4K

![img](https://cdn.udelivrs.com/2025/04/4d05a0968e264ba49abad3d09f39127e_1744194422935.jpg)<br>

(Comparison between local normal disk and local SSD)

**Test Details**

> Tool: fio
> 
> Official website:
> 
> <http://freecode.com/projects/fio>
> 
> <http://brick.kernel.dk/snaps/>

**Note: For performance testing, it is recommended to test by writing directly to the raw disk to obtain more accurate data. However, direct raw disk testing may damage the file system structure and cause data loss. Ensure that data on the disk has been backed up before testing.**

Block size: 4kb / 512kb

Queue depth: 128

fio.conf configuration:

```
[global]
ioengine=libaio
iodepth=128
time_based
direct=1
thread=1
group_reporting
randrepeat=0
norandommap
numjobs=32
timeout=6000
runtime=120

[randread-4k]
rw=randread
bs=4k
filename=/dev/sdb   Note: /dev/sdb is the device name of the target test disk
rwmixread=100
stonewall

[randwrite-4k]
rw=randwrite
bs=4k
filename=/dev/sdb
stonewall

[read-512k]
rw=read
bs=512k
filename=/dev/sdb
stonewall

[write-512k]
rw=write
bs=512k
filename=/dev/sdb
stonewall
```

How to use: shell$\> fio fio.conf