Slow transfer speed due to SSD cache acceleration

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pokrakam
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Re: Slow transfer speed due to SSD cache acceleration

Post by pokrakam » Mon Apr 17, 2017 5:21 am

@peter247 and scotland21 - or anyone else who has experienced the slowdown issue: as a matter of interest, what SSDs are you using?

QTS 4.3 is quite a major change, would also be interesting to hear if anyone with this issue has upgraded to the beta yet and how it performs.

scotland21
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Re: Slow transfer speed due to SSD cache acceleration

Post by scotland21 » Mon Apr 17, 2017 6:00 am

On my TVS-871 I use 2 Samsung SSD 750 EVO 500GB.
On my TVS-471U I use Samsung SSD 840 EVO 250GB mSATA and a Samsung SSD 850 EVO 250GB mSATA.
On my TS-853pro I use SAMSUNG MZ7LN256HCHP-000L7 and a SAMSUNG MZ7PD256HAFV-000H7.
On My TVS-663 I use 2 SanDisk X110 60GB.
I run all my cache on raid 0 read write to maximize capacity and hopefully speed.
TS-509pro 4.2.4, TS-809pro 4.2.4, TS-459II 4.2.4,TS-559II 4.2.4
TVS-663 4.3.3.0095, TS-853pro 4.3.3.0095, TVS-871 4.3.3.0095
Scotland21 8)

cryptochrome
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Re: Slow transfer speed due to SSD cache acceleration

Post by cryptochrome » Mon Apr 17, 2017 4:24 pm

The bug is still very much present in 4.3.3

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Trexx
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Re: Slow transfer speed due to SSD cache acceleration

Post by Trexx » Mon Apr 17, 2017 10:33 pm

I am running m.2 Crucial MX300 525GB SATA.
Paul

Model: TS-877-1600 FW: 4.4.3.x
QTS (SSD): [RAID-1] 2 x 1TB WD Blue m.2's
Data (HDD): [RAID-5] 6 x 3TB HGST DeskStar
VMs (SSD): [RAID-1] 2 x 500GB Evo 860
Ext. (HDD): TR-004 [Raid-5] 4 x 4TB HGST Ultastor
RAM: Kingston HyperX Fury 64GB DDR4-2666
GPU: EVGA GTX 1060 6GB
UPS: CP AVR1350

Model:TVS-673 32GB FW: 4.4.3.x Test/Backup Box
Model:TS-228a FW: 4.4.3.x Test/Backup Box
-----------------------------------------------------------------------------------------------------------------------------------------
NAS RAID Rebuild Times | Live QTS Videos | | QNAP NAS Guide | Information needed when you ask for HELP | QNAP Links, Tutorials, etc.
2018 Plex NAS Compatibility Guide | QNAP Plex FAQ | Moogle's QNAP Faq

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AcerTravel
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Location: Going From Mars To Saturn

Re: Slow transfer speed due to SSD cache acceleration

Post by AcerTravel » Fri Apr 21, 2017 3:07 am

Hello,
I'm not an QNAP employee, but synology as it's own problems and issues to.... read first it's own forum and you see... what i'm talking about....
TS-212
TS-453PRO 8GB + UX-500P
TS-453A 8GB + UX-800P

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skypx
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Re: Slow transfer speed due to SSD cache acceleration

Post by skypx » Fri Apr 21, 2017 4:37 am

Obviously qnap and synology's implementation of ssd cache isn't working well. If anyone is interested in speed see my sig. Don't forget to disable "Enable Asynchronous I/O" as it will slow transfer rates on fast networks.

QNAP TVS-871 17 April 2017.JPG


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TVS-871 i7 16GB Ram
Firmware 4.4.2.1270 build 20200410
8x HGST HUH721212ALN600 LEGNT3D0 RAID 5
QNAP Network LAN-10G2T-X550T2
Cisco SG350XG-2F10

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hakannordell
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Re: Slow transfer speed due to SSD cache acceleration

Post by hakannordell » Thu May 04, 2017 1:38 am

I have just the same problem that I was going to start exploring when I read this thread. The tests below are from TS-1635 and UX500p via USB, with Samsung Evo 512 MB as cache. I made a transfer of a number of movies and turn off the cache :shock:

Image
With and without cache
[Plex Runner] QNAP TVS-471 (QTS 4.3.4.0435), Intel Core i7-4790S, 16GB RAM, 768GB 850 Pro SSD for System and Transcoding, RAID-1, Shared APC 750
[Data Holder and Plex Runner] TS-1685 (QTS 4.3.4.0435), Qtier, 16GB RAM, 1,5TB 850 EVO M2, 512GB 850 Pro and 512GB EVO SSD, 32TB RED RAID-5,, Shared APC 750 and 10 GbE SFP+
[Master Backup] QNAP TS-1635 (QTS 4.3.4.0435), 16GB RAM, 512GB Pro SSD, 24TB RED RAID-5, Shared APC 750 and 10 GbE SFP+
[Seconary Backup] QNAP UX-500P, 20TB RED RAID-5, Shared APC 750
[Torrent Runner] QNAP TS-431 (QTS 4.3.4.0435), 0TB RED RAID-1, Shared APC 750
[Off-Site Backup] NetGear ReadyNAS Ultra 6 (ReadyNAS OS 6.7.5), Seagate 12TB RAID-0, Singel APC SC 620
[Other Cool Stuff] Linksys LRT224 DualWAN, Fibaro HC2

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gruffvaughan
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Re: Slow transfer speed due to SSD cache acceleration

Post by gruffvaughan » Thu May 04, 2017 9:21 pm

I also had this problem after turning on Cache Acceleration with a pair of 128GB mSATA SSDs (provided with the system) in RAID1 for sequential r/w. Attempting to transfer from an external USB3 drive was giving me ~20Mb/s. I turned off the cache, and after flushing, performance improved to ~110Mb/s with latency dropping from 15,000ms to 200ms.

Can I make better use of the mSATA SSDs? They're currently just sat there twiddling their thumbs.
NAS: TVS-EC2480U-SAS-RP || 4.3.3.0154 Build 20170413 || 10 x Seagate 6TB ST6000NM0095 12Gbps || RAID6
CPU: Intel(R) Xeon(R) CPU E3-1246 v3 @ 3.50GHz || Memory: 8GB
Cache: 2 x ATA ADATA_IXM35-128GM (mSATA) (Disabled due to poor performance!)
Network: 802.3ad and 10 GbE SFP+ || UPS: APC Smart UPS 1500

Image
Video Production || Cardiff, UK
http://stormandshelter.com

cryptochrome
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Re: Slow transfer speed due to SSD cache acceleration

Post by cryptochrome » Thu May 04, 2017 9:35 pm

Yea, just create a new volume from the SSDs and you can use them just like any other disk in the system.

kherr4377
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Re: Slow transfer speed due to SSD cache acceleration

Post by kherr4377 » Thu May 04, 2017 9:40 pm

Trexx wrote:I am running m.2 Crucial MX300 525GB SATA.


i have a very similar setup. i looking to get the same m.2 for r/w cache (mostly write) how is your performance Trexx
Production :
TVS-673 4.3.4 0387
4 X 3TB WD RED : 1 X 4TB HGST DESKSTAR R5
32GB
LAN-10G1SR-D, FiberHal for Cisco SFP-10G-SR
NETGEAR ProSAFE SS3300-28X

Backup :
TS-469L 4.3.4 0387
4 X 3TB WD RED R5
3GB
Located detached garage .. cheap offsite solution ...

2nd TS-469L awaiting drives and reassignment for front-line duty .......

scotland21
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Re: Slow transfer speed due to SSD cache acceleration

Post by scotland21 » Fri May 12, 2017 5:41 pm

@pokrakam Are Qnap continuing their investigations on your system?
If not does anyone know whether they have accepted and made the issue public.
I have currently turned off my cache on both my TVS871 and TS-853, they now have expensive drives sitting doing nothing.
TS-509pro 4.2.4, TS-809pro 4.2.4, TS-459II 4.2.4,TS-559II 4.2.4
TVS-663 4.3.3.0095, TS-853pro 4.3.3.0095, TVS-871 4.3.3.0095
Scotland21 8)

pokrakam
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Re: Slow transfer speed due to SSD cache acceleration

Post by pokrakam » Fri May 12, 2017 6:53 pm

No feedback since my last post. I have however upgraded to QTS 4.3, planning to do another series of tests when I have the capacity (have time and NAS not in use) and give them another nudge, as initial quick tests confirmed cryptochrome's observation that 4.3 doesn't fare much better. Hopefully this weekend.

scotland21
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Re: Slow transfer speed due to SSD cache acceleration

Post by scotland21 » Fri May 12, 2017 8:26 pm

Just to confirm my findings have been on firmware 4.3, currently on 4.3.3.0174 which I had hoped would have included an indication that the cache performance had been addressed in the change log.
This issue isn't mentioned so I assume they haven't either fixed the issue or if they have don't want to admit it.
I still see slow copy speeds when transferring data which is why I turned it off on the 3 nas's that support SSD cache.
TS-509pro 4.2.4, TS-809pro 4.2.4, TS-459II 4.2.4,TS-559II 4.2.4
TVS-663 4.3.3.0095, TS-853pro 4.3.3.0095, TVS-871 4.3.3.0095
Scotland21 8)

cryptochrome
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Re: Slow transfer speed due to SSD cache acceleration

Post by cryptochrome » Fri May 12, 2017 8:36 pm

Don't count on QNAP for this. When I had my support ticket still open, they weren't able to replicate the problem (allegedly). That basically killed any further discussion. I wouldn't be surprised if they didn't understand the problem at all.

gregoinc
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Re: RE: Re: Slow transfer speed due to SSD cache acceleration

Post by gregoinc » Sat May 13, 2017 5:45 am

cryptochrome wrote:Don't count on QNAP for this. When I had my support ticket still open, they weren't able to replicate the problem (allegedly). That basically killed any further discussion. I wouldn't be surprised if they didn't understand the problem at all.

I agree with above. I dont think QNAP understand the issue... or... they just aren't devoting resources to look at it, as there are probably other priorities. My advice, use the read only cache and move on. Maybe... just maybe, one day QNAP will get with the program and understand read/write caching is a function thier customers want. Or by then we'll all have 10Gb and PCIE SSD only QNAP's and it wont matter

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