What helps with improving Samba speeds?

[Sirius]

I've attached a screenshot of the speeds I get currently and I'm wondering if anything can be done to improve the 4KiB speeds. The picture with the faster speeds is using iSCSI instead of SMB.

I'm using a 4930k as the CPU currently so I've considered using a Xeon with a much higher boost clock (and a better mobo with ECC) as I believe SMB benefits best from a high CPU clock?

Please note this is for a single user system, so I'm after maximising performance for a single user. Some shares may be used by other people but the speeds on those aren't as essential.

Currently I'm using 1gigE but I do plan to use 10gigE once I get the NICs and accessories. It'd be nice to optimise the QD1 4KiB speeds too, but I'm guessing not much can be done about those speeds.

Thank you for any advice! :)

 

[artlessknave]

platter drives max out at ~200 MB/s. zfs caching provides a speedup, and disk arrangement has an effect (more vdevs = more speed), but in general you will see spikes of 5gbe with long transfers more around 2-300 MB/s. iperf shows me the full 10gbe speed, but I rarely get very close to it. SSD's should change that, but the size isn't on par with platters.
it was admittedly disappointing but 300MB/s is still faster than 100, and anything that is cached can go way faster

 

[Sirius]

For extra clarification, these are the speeds I get when using a VM located on the same server as the FreeNAS install...

I'm fine with the sequential speeds but I'd really like to improve the SMB 4KiB speeds. As you can see iSCSI is in some cases over twice as fast.