[question] Can vistator run on HDD without considering performance?

[lnsyyj]

Hi @vitalif ,

We have a requirement that we want to use vitastor on HDD, because now most customers consider the large capacity of HDD.

1. Can vistator run on HDD without considering performance?
2. Can it be deployed to distribute wal on SSD and data on HDD?

[vitalif]

Hi, SSD journal+meta + HDD data is totally fine, it even has "write throttling" feature which allows to smooth random write performance, see https://github.com/vitalif/vitastor/blob/master/docs/params/osd.yml#L259 (it's the source of parameter docs which I'm currently writing) - throttle_small_writes, throttle_target_iops, throttle_target_mbs, throttle_target_parallelism

HDD-only will work, but there is a high chance that it will be slow because Vitastor doesn't have any optimisations for metadata writes on HDDs. I haven't tested what's "slow" in this case though :-)

[lnsyyj]

Awesome, I think that's what most users want.

[vitalif]

I made some tests with HDD only since then and surprisingly Vitastor works really well. So now HDD-only is also a supported configuration.