diskfio KVM QEMU testing on Ubuntu 20.04 via the Phoronix Test Suite. 2 x 107GB QEMU HDD: Processor: 8 x QEMU Virtual 2.5+ (8 Cores), Motherboard: Red Hat KVM (1.16.0-3.module_el8+310+72016cce BIOS), Chipset: Intel 440FX 82441FX PMC, Memory: 2 x 16384 MB RAM, Disk: 2 x 107GB QEMU HDD, Graphics: Red Hat QXL paravirtual graphic card, Network: Red Hat Virtio device OS: Ubuntu 20.04, Kernel: 5.4.0-65-generic (x86_64), Desktop: GNOME Shell 3.36.9, Display Server: X Server, Vulkan: 1.1.182, Compiler: GCC 9.4.0, File-System: ext4, Screen Resolution: 1024x768, System Layer: KVM QEMU Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: No - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 21766.36 |================================================ Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: No - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 5442 |==================================================== Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: No - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 22344.42 |================================================ Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: No - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 5586 |==================================================== Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: Yes - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 23761.29 |================================================ Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: Yes - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 5940 |==================================================== Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: No - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 25250.17 |================================================ Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: No - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 6313 |==================================================== Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: Yes - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 25843.64 |================================================ Flexible IO Tester 3.35 Type: Random Read - Engine: Sync - Buffered: Yes - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 6461 |==================================================== Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: No - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 25069.42 |================================================ Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: No - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 6267 |==================================================== Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: Yes - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 449303.27 |=============================================== Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: Yes - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 112326 |================================================== Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: Yes - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 449788.74 |=============================================== Flexible IO Tester 3.35 Type: Random Write - Engine: Sync - Buffered: Yes - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 112447 |================================================== Flexible IO Tester 3.35 Type: Random Read - Engine: IO_uring - Buffered: No - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory Flexible IO Tester 3.35 Type: Sequential Read - Engine: Sync - Buffered: No - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 68943.22 |================================================ Flexible IO Tester 3.35 Type: Sequential Read - Engine: Sync - Buffered: No - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory IOPS > Higher Is Better 2 x 107GB QEMU HDD . 17236 |=================================================== Flexible IO Tester 3.35 Type: Random Read - Engine: IO_uring - Buffered: No - Direct: Yes - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory Flexible IO Tester 3.35 Type: Random Read - Engine: IO_uring - Buffered: Yes - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: Default Test Directory Flexible IO Tester 3.35 Type: Random Read - Engine: POSIX AIO - Buffered: Yes - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: / MiB/s > Higher Is Better 2 x 107GB QEMU HDD . 21724.23 |================================================ Flexible IO Tester 3.35 Type: Random Read - Engine: POSIX AIO - Buffered: Yes - Direct: No - Block Size: 4KB - Job Count: 1 - Disk Target: / IOPS > Higher Is Better 2 x 107GB QEMU HDD . 5431 |====================================================