Severe performance drop when upgrading to 11.1

[SSEvans]

(The BackGround)
I built a NAS in late 2016 to act as a plex media server. This is the only function i need the machine to perform. When i built it i think the version of freeNAS was 9.3, it ran beautifully. It wasn't the fastest machine on the plane but it could support 5 or 6 simultaneous streams and the write speed was acceptable. The set up was and still is

(The Machine)
ASRock AM1H-ITX AM1 SATA 6Gb/s USB 3.0 HDMI Mini ITX AMD Motherboard
AMD Sempron 3850 Kabini Quad-Core 1.3 GHz Socket AM1 25W SD3850JAHMBOX Desktop Processor AMD Radeon HD 8280
2 X HyperX FURY 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10600) Desktop Memory Model HX313C9FRK2/16
4 X WD Red 3TB NAS Hard Disk Drive - 5400 RPM SATA 6 Gb/s 64MB Cache 3.5 Inch - WD30EFRX
Corsair CX Series, CX430M, 430 Watt (430W), Semi Modular Power Supply, 80+ Bronze Certified

the drives were running in Raid Z1.

(The Problem)
The machine has been shelved for over a year and i recently pulled it out to get it up and running again. I ran into some issues upgrading so i transferred the data to a few spare drives i have and started with a clean slate. I installed 11.1 and got my plex plugin up and running. This is where i ran into the issue, when trying to move the media back to the NAS the write speed is abysmal!!! I am on a mac and can't see what the exactly what it is but it took over 3 minutes to move a single 1Gb movie to the drives. Also when attempting to stream this single movie the load time is excessive, i haven't even tried more than one at this point.
-I am transferring everything over wifi. The Router is not the bottleneck.

(The Question)
1) Is there a simple tweak to speed the machine up?
2) Is the new version to much for my hardware?
3) Will upgrading my CPU increase the performance of my machine substantially? ( AMD Athlon X4 845 with AMD quiet cooler Quad-Core Socket FM2+ 65W AD845XACKASBX Desktop Processor)

Thanks in advance!

 

[SSEvans]

1 gigabyte in 3 minutes. I make that over 40 megabits per second. It seems plausible that your wifi network is the limiting factor. Are you sure it isn't?

Also your CPU is going to struggle if Plex is transcoding.

the reason i say it is not, is because when i was transferring the data off of the NAS i was able to transfer all 1.75 TB in 50 hours. I am not great with the conversions but i don't think that adds up. Furthermore i am currently testing a 18 GB transfer and it is bouncing around 2 hours of transfer time

 

[anmnz]

the reason i say it is not, is because when i was transferring the data off of the NAS i was able to transfer all 1.75 TB in 50 hours. I am not great with the conversions but i don't think that adds up. Furthermore i am currently testing a 18 GB transfer and it is bouncing around 2 hours of transfer time

1.75 TB in 50 hours is only twice as fast or so -- if anything has happened to interfere a bit with the wireless network, that could definitely explain this kind of difference.

Meanwhile if you are wondering if your CPU is a bottleneck, just look at CPU graphs in the UI under "Reporting" to get an indication whether it's working hard.