Yet another issue with read/write speed. Fast write, slow read

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knowfuture
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Yet another issue with read/write speed. Fast write, slow read

Post by knowfuture »

Hi all,

I've been browsing through the forums to find my answer but many of the solutions/suggestions did not seem to solve my issue. I was hoping I can get some guidance.

I recently purchased a QNAP TS-473a with 4 x 16 TB Seagate Ironwolf Pro HDDs.
I am using QTS with RAID 10 (ext4), 1 GbE wired connection (yes, I know, I am not with the times), without SSD cache.
My write speed is saturating the GbE speed at about 110-115 MB/s, but my read speed is always somewhere between 20-40 MB/s. I've seen it go down as low as 10 MB/s. I am using SMB3 without encryption and 1500 MTU. I've tried changing the jumbo frame size to 9000 MTU, but it did not seem to do much (changed my router and PC to 9000 MTU as well).

I tested the continuity of all the ethernet cables and performed an internet speed test on my NAS using tianon/speedtest. I am getting ~300/300 Mbps, which is about my internet speed. For these reasons, I do not think it is a connection issue.

I ran qcli_storage -t and qcli-storage -T and here are the results:
qcli_results.png
SMART tests on my hard drives shows that they are all healthy and the performance test shows sequential read speeds of ~250 MB/s
I performed the IOPS test a few days ago and they were all somewhere between 70-90 if I recall correctly. (I am currently running a complete disk health test and it is taking a while and do not want to stop midway).
hdd_readtest.png
Any help is appreciated.

On a side note, I am concerned that my HDD is failing (I just got these less than 2 months ago). This is my first time buying 16 TB HDDs and they make a TON of noise. On boot up, I've heard almost like a inkjet printer belt type of noise, which I did not think was normal. I am hoping this complete disk health test will be able to tell me something...
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dolbyman
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Re: Yet another issue with read/write speed. Fast write, slow read

Post by dolbyman »

werid . similar thread from earlier today ..also a x73a unit

viewtopic.php?f=25&t=165761
knowfuture
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Re: Yet another issue with read/write speed. Fast write, slow read

Post by knowfuture »

dolbyman wrote: Thu Mar 24, 2022 9:47 am werid . similar thread from earlier today ..also a x73a unit

viewtopic.php?f=25&t=165761
I saw this too! I would be happy to have that ratio of write/read speed.
I am hoping I'm just doing something stupid...
peca89
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Re: Yet another issue with read/write speed. Fast write, slow read

Post by peca89 »

I'm experiencing the same issues with both old 453Be and new 453D.

Issue with 453Be documented here 3 years ago and it did not change:
https://www.reddit.com/r/qnap/comments/ ... _it_reads/

I've tested yesterday with brand new 453D and QNAP 2.5Gb switch, except this time read speeds are around 150 MB/s while write speeds are around 250 MB/s.
TS-453Be
crhodes325
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Re: Yet another issue with read/write speed. Fast write, slow read

Post by crhodes325 »

Having the same issue with my QNAP TS-453D with respect to my Read/Write speeds. Set up an OpenSpeedTest using the Container Station App, from the NAS to my desktop. 470 Mbps download, 940 Mbps upload, across an ethernet connection. Tried switching over to wireless to see if I would experience the same issue, yep half the speed. Anyone have any ideas?
Flexerl
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Re: Yet another issue with read/write speed. Fast write, slow read

Post by Flexerl »

Did this ever get resolved?
geekm0nkey
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Re: Yet another issue with read/write speed. Fast write, slow read

Post by geekm0nkey »

I came to the forum with the same issue to report. I have a TS-433, raid 5. Initially, the system works as intended but some catalyst happens and then the reads become extremely slow. Like in the Kb range. There is a twist. I think this affects the samba share. I have a plex server that uses CIFS to map to the NAS and video playback is normal (so it would seem) but a windows network share is super slow. A NAS restart fixes the issue until whatever causes it happens again. I have not tried just restarting samba on the NAS to see if that works. The restart of the NAS is not ideal because of the length of time it takes.
PeterT1959
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Joined: Mon Nov 19, 2012 11:16 am

Re: Yet another issue with read/write speed. Fast write, slow read

Post by PeterT1959 »

Fyi. Cifs and samba are the same
Tomgh
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Re: Yet another issue with read/write speed. Fast write, slow read

Post by Tomgh »

I had a similar issue. Tested with AJA and the NAS 'suddenly' had ~200 MB/s write and only 50 MB/s read. Only, the 'suddenly' was after a fresh Windows installation. And it seemed that my 10 Gb network adapter still needed it's drivers. It did work without the specific drivers, which caused the confusion, but it had slow read speed apparantly. With drivers I'm back to about 400 MB/s read (on encrypted Raid 5 storage).
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