ZFS performance bottlenecks: CPU or RAM or anything else?

[Steven Hartland]

Tbh if the results were from more than 6 months ago they are likely quite
out of date as things have changed quite significantly in that period,
so retesting would be advised.

On Tuesday, 17 May 2016, Freddie Cash <fjwcash at gmail.com> wrote:

> On Tue, May 17, 2016 at 2:11 PM, Steven Hartland <steven at multiplay.co.uk
> <javascript:_e(%7B%7D,'cvml','steven at multiplay.co.uk');>> wrote:
>
>> Raidz is limited essential limited to a single drive performance
>> per dev for read and write while mirror is single drive performance for
>> write its number of drives for read. Don't forget mirror is not limited to
>> two it can be three, four or more; so if you need more read throughput you
>> can add drives to the mirror.
>>
>> To increase raidz performance you need to add more vdevs. While this
>> doesn't have to be double i.e. the same vdev config as the first it
>> generally a good idea.
>>
>> Don't forget that while it rebalances write performance of a multi vdev
>> raidz will be limited to the added vdev.
>>
>
> ​Everybody is missing the point of the OP.
>
> They're not asking for ways to improve the performance of a raidz-based
> pool; they're asking why they get different performance metrics from the
> exact same pool when they change the CPU and RAM.
>
> And, more importantly, why a Core-i3-based system shows better performance
> than a Core-i7-based system.​  Is there something inherent to the way ZFS
> works that favours one setup over another (lower CPU core counts running at
> higher speeds is better/worse than higher CPU core counts running at lower
> speeds; more RAM channels is better/worse; things like that).
>
>
> --
> Freddie Cash
> fjwcash at gmail.com <javascript:_e(%7B%7D,'cvml','fjwcash at gmail.com');>
>