Slow read speeds


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Hi!

 

Im getting very slow read spees from my unraid array. I have 6 WD Green 2tb drives and one Samsung HD204UI.

 

Processor : Intel® Core™2 Quad CPU Q8400 @ 2.66GHz

Memory : 8Gb DDR2 800mhz

 

 

 

I have a gigabit network and all my cables should be fine...

 

Heres my ethtool eth0 :

Settings for eth0:

        Supported ports: [ TP ]

        Supported link modes:  10baseT/Half 10baseT/Full

                                100baseT/Half 100baseT/Full

                                1000baseT/Full

        Supported pause frame use: No

        Supports auto-negotiation: Yes

        Advertised link modes:  1000baseT/Full

        Advertised pause frame use: No

        Advertised auto-negotiation: Yes

        Speed: 1000Mb/s

        Duplex: Full

        Port: Twisted Pair

        PHYAD: 0

        Transceiver: internal

        Auto-negotiation: on

        MDI-X: Unknown

        Supports Wake-on: pg

        Wake-on: d

        Current message level: 0x00000000 (0)

 

        Link detected: yes

 

The problem is that I'm getting read speeds between 15 MB/s and 30 MB/s. My write speeds are usually about 80 MB/s. I'm trying to write over SMB from my Windows 10 desktop machine (2500k 16gb SSD).

 

Could you guys tell me where the problem could be?

 

tower-diagnostics-20160530-0821.zip is attached.

 

 

tower-diagnostics-20160530-0821.zip

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This is from unraid to desktop 6,5gb .mkv

qS18zQy

 

This is from desktop to unraid

iXNwP76

 

Heres drivespeed.sh results :

 

pUBHuA8

 

I got two more 2tb drives so i can do some testing. I managed to get one transfer from desktop to SNAP mounted 2tb WD green drive over 100mb/s. So the problem must be somewhere in the array...

 

I added temporary cache drive and got 100mb/s speeds halfway throught that 6,5gb file but after that speeds dropped to ~20mt/s...

 

So problem should not be in my network because i can get 100mb/s speeds on some circumstances?

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I used to have Atom 330 based system but it was very slow so i upgraded to LGA775 C2Q system with 8gb of ram. My unraid installation is still the same from that Atom based system, so should i try to make new installation? Could that help? And if so, should i install beta or stable?

 

Now i have 2 empty 2tb drives so i have some flexibility to even make a new array but transferring all those terabytes takes so much time that i would like to resolve this in some another way.

 

 

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I used to have Atom 330 based system but it was very slow so i upgraded to LGA775 C2Q system with 8gb of ram. My unraid installation is still the same from that Atom based system, so should i try to make new installation? Could that help? And if so, should i install beta or stable?

 

Now i have 2 empty 2tb drives so i have some flexibility to even make a new array but transferring all those terabytes takes so much time that i would like to resolve this in some another way.

 

You problem looks network related, if you have another PC/laptop try copying from unRAID preferably using a different cable and switch.

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I used to have Atom 330 based system but it was very slow so i upgraded to LGA775 C2Q system with 8gb of ram. My unraid installation is still the same from that Atom based system, so should i try to make new installation? Could that help? And if so, should i install beta or stable?

 

Now i have 2 empty 2tb drives so i have some flexibility to even make a new array but transferring all those terabytes takes so much time that i would like to resolve this in some another way.

 

You problem looks network related, if you have another PC/laptop try copying from unRAID preferably using a different cable and switch.

 

But i can manage to get full 1gbps speeds (sometimes) when copying from drive that is not part of my array.

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But i can manage to get full 1gbps speeds (sometimes) when copying from drive that is not part of my array.

 

You should get it always, assuming you're transferring large files, reading from the array is like reading from a single disk.

 

Yes, but because i can see 100mt/s speeds sometimes i figured that the problem should be elsewhere. In fact i tired with another cable and without my switch. Maybe i should investigate some more with different cables, but all cables should be CAT5e..

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1st one is from unraid to desktop, 2nd from desktop to unraid. I have no idea what is going on... disconnected my switch and used only my routers ports..

1st one look like normal 1GB read speed from unRAID. 2nd one looks like normal write speed to unRAID parity array.
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1st one is from unraid to desktop, 2nd from desktop to unraid. I have no idea what is going on... disconnected my switch and used only my routers ports..

1st one look like normal 1GB read speed from unRAID. 2nd one looks like normal write speed to unRAID parity array.

 

Is that 1st pictures slow speed at the beginning of the transfer normal?

 

EDIT:

 

I did a quick test. All drives were spun down and after i transfered 300mt file to array, last data drive and parity got spun up. Should that be the case if cache drive is installed?

 

It seems that different files from my array get very different read speeds...

 

2nd pictures speed is a odd because i have a cache drive installed... Maybe it is not working correctly then..

 

2ND EDIT:

 

I did not know that i had to enable Cache drive from shares settings, now it seems to be working..

 

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There were 3 support threads here, and I have split them apart, with similar subject titles.  Users, PLEASE do not take over someone else's support thread, even if your problem *sounds* exactly like theirs.  You can comment on *their* problem, but if you want support for *your* problem, start a thread just for you.  Problems that sound alike rarely are, and mixing them up can sometimes confuse the helpers!  Help us help you!

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