1 SSD and 2 HDD - best storage setup?

[alexc]

It as a bit unusual to configure such a host but I did the server setup (ZFS is used to be self-minded somewhat like "ok, I know how to do that, don't mind" and it just works - not to mention that is should be tuned for load).

It you permit I'd ask the question for idea I heard one day: is I, say, run VM that is simple LAMP server, I should create several ZFS pool with different recordsize (if I recall it right), and put MySQL data on pool-tuned-for-mysql-data-storing, put web files on web-stogare-optimized-pool etc. Do you have any experience with it?

I also not sure if compression etc should be enabled for all data pool, but ZFS guru says it seems to be good idea to use it anytime I can.

 

[LnxBil]

It you permit I'd ask the question for idea I heard one day: is I, say, run VM that is simple LAMP server, I should create several ZFS pool with different recordsize (if I recall it right), and put MySQL data on pool-tuned-for-mysql-data-storing, put web files on web-stogare-optimized-pool etc. Do you have any experience with it?

Yes, not explicitely with PVE, but with Docker-based hosts on ZFS with Postgres. There are also tweaks to have it running faster than ext4, because some features like "write at once and do not screw the write up" is atomic with ZFS, but has to be ensured e.g. on ext4 which is slower. So yes, ZFS can be much faster if it is tuned to the application at hand.

ZFS will have tremendously increased performance with higher recordsizes (and the corresponding files) and compression will be even better (if the files are compressible e.g. large XML files). So you webserver example is also true for big, compressible files (HTML, JS, CSS) but not for e.g. images or videos, which are intrinsically already highly compressed.

 

[LnxBil]

I also not sure if compression etc should be enabled for all data pool, but ZFS guru says it seems to be good idea to use it anytime I can.

Yes. If ZFS detects, that the file cannot be compressed (or does not yield better compression than the uncompressed block), it will not store it compressed.