Low Read Speed

[Gaspetaahl]

Hey,

so my FreeNAS is working for 2 weeks now, but I have problems with low read speeds (lower than writing). I tested my Linux Laptop and my Windows Desktop (both GBit Lan using samba)

Desktop:
Read: 50-60MBit/s
Write 115 MBit/s
Laptop:
Read: 55MBit/s
Write: 55 MBit/s

Why is reading slower than writing? Shouldn't it be the other way around? Why is is generally slower on my Laptop? I already looked at the reporting graphs but I dont really know what to look for.

Hardware:
FreeNAS-11.1-U6
Serverboard Supermicro X10SLL-F
Intel Xeon E3-1231 v3 3,40GHz Turbo 3,80GHz
2 x HMT41GU7AFR8C-PB (16GB)
5 x WD RED 8TB/ 4 of them from WD MyBooks in a RAIDZ2

Also I activated encryption. for the pool

Code:

root@freenas:~ # zpool status
  pool: Volume1
 state: ONLINE
  scan: none requested
config:

		NAME												STATE	 READ WRITE CKSUM
		Volume1											 ONLINE	   0	 0	 0
		  raidz2-0										  ONLINE	   0	 0	 0
			gptid/5ad8d4bb-e011-11e8-8258-0025905a4e61.eli  ONLINE	   0	 0	 0
			gptid/5b6f1f6d-e011-11e8-8258-0025905a4e61.eli  ONLINE	   0	 0	 0
			gptid/5c139d07-e011-11e8-8258-0025905a4e61.eli  ONLINE	   0	 0	 0
			gptid/5cad1cb1-e011-11e8-8258-0025905a4e61.eli  ONLINE	   0	 0	 0
			gptid/5d524660-e011-11e8-8258-0025905a4e61.eli  ONLINE	   0	 0	 0

errors: No known data errors

  pool: freenas-boot
 state: ONLINE
  scan: scrub repaired 0 in 0 days 00:00:31 with 0 errors on Sat Nov 17 03:45:31 2018
config:

		NAME		STATE	 READ WRITE CKSUM
		freenas-boot  ONLINE	   0	 0	 0
		  da0p2	 ONLINE	   0	 0	 0

errors: No known data errors

 

[sretalla]

You haven't finished giving your hardware details (how much RAM, how are the HDDs connected, which version of FreeNAS, for example).

It certainly isn't matching the theory of how a system will work when properly configured (also the experience of most of us in the forum).

You may also want to look at the performance charts in the GUI to see obvious things like Swap usage and the disk % busy measures.

It would also help us to see the output of zpool status

 

[Gaspetaahl]

I added the information in the top post.
Also I tried to enable TLER on the MyBook drives as describe here: https://www.reddit.com/r/8tbEasystore/comments/7h292h/wd80efzx_wd80efax_wd80emaz_wd80ezaz/
with smartctl -l scterc,70,70 <disk> but it also fails (every smartctl command fail with this error)

Code:

root@freenas:~ # smartctl -d sat -l scterc,70,70 ada1
smartctl 6.6 2017-11-05 r4594 [FreeBSD 11.1-STABLE amd64] (local build)
Copyright (C) 2002-17, Bruce Allen, Christian Franke, www.smartmontools.org

Read Device Identity failed: Input/output error

A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options.

 

[HoneyBadger]

I assume the HDDs are connected directly via the onboard SATA controller? Your zpool status also is not showing any pools other than the boot pool - it should show the actual data as well.

With regards to the speeds, what are the model of network cards on your client machines? Laptops especially are notorious for using cheap NICs that often can't sustain good throughput - although half of potential max is quite the reduction, even for something as weak as a Realtek.

Writes will frequently be faster as the default for SMB from those clients would be asynchronous - meaning that they'll be acknowledged once they hit RAM - but the reads might actually have to go to disk if it's not cached. It's possible that highly fragmented data could be slower to read than to write.

 

[Gaspetaahl]

Everything connected via onboard SATA yes
My Laptop uses this Network Controller:
Ethernet controller: Intel Corporation Ethernet Connection (3) I218-LM (rev 03)

I was also able to get 115MBit/s when I transferred a 30GB file to the NAS from my PC (so the RAM was full then)

I also edited the full zpool status at the top

Any tips on smartctl?

 

[HoneyBadger]

Try dropping the -d sat from your smartctl parameters - if they're internally connected they're more likely to be addressed as regular ATA, I normally only need the sat type when I'm trying to pass SMART over a USB bridge.

For your transfer speeds, what kind of speed do you see if you just dd a file to /dev/null? That would take the network out of it.