On 29/04/2020 15:37, Sad Clouds wrote:
On Wed, 29 Apr 2020 09:17:54 +0100
Chavdar Ivanov <[email protected]> wrote:
On my VirtualBox 6.1.6 guest running -current amd64 I get:
$ time cat 80mb > /dev/null
cat 80mb > /dev/null 0.00s user 0.02s system 98% cpu 0.021 total
dd if=/dev/zero of=out bs=1m count=10000
do you get similar I/O throughput on NetBSD and Linux guests?
Make sure you use the fdatasync option on linux when using dd for
writing. Otherwise it just writes as much as it can to cache and then
returns without actually waiting for the write to complete falsely
inflating the performance.
I haven't tried with anything later than 7 but I use virtual box hosted
on windows a lot with ahci storage emulation. In the last tests I did I
was getting 100MB/s write performance with both Ubuntu (kernel 4.4) and
NetBSD 7. For reference the underlying disk in that case was a 2TB ATA
attached to an AHCI controller.
I can spin up a 9.x VM and test that relatively easily. current would
take a little longer as I'd have to build it first :)
Mike
