NVME SSD Cache on Synology Diskstation NAS (DS1621+) and Benchmark

[@wfp9378]

2:46 actually makes a massive difference with Plex. Staggering actually, but not with the playback. It’s the browsing experience, tons of small files as you scroll through the files you have. It also makes a big difference for the home user when browsing the photos app.

[@StephenWagner]

Hey WFP, thanks for dropping that comment, that's good to know and I'm sure it'll help others! :)

[@andrewenglish3810]

@SW The Tech Journal i notice you are using RAID 5 and not SHR1, is there a reason for that?

[@StephenWagner]

I'm not too familiar with SHR, however I chose RAID 5 because of my familiarity of it, as well after a bit of research it sounded like SHR may degrade IOPS and transfer speeds.

[@fretbuzzly]

RAID 5 has slightly better performance versus SHR1 because there is some overhead with SHR1. This is why on the Synology "enterprise" NASes SHR is not offered.

[@medbenmedben]

Hello, I have a DS918+ with 2 ssd cache that I have on read and write. In the storage manager, they are both attached to only one volume ! 🤔 1- Does that mean that only this volume benefits from the cache and not the others ? 2- And do operations like : extracting a huge zip file to the same disque benefits frome the ssd cache ? Thanks 😊

[@StephenWagner]

Hi Neuromatiq, It sounds like the cache is only being used on the single volume. I could be wrong, but in newer versions of DSM, you may be able to attach the cache to multiple volumes, however this might only be on the higher end devices (I'm not too sure). It's hard to say for sure, but if you're accessing a ZIP file over a network share, there is a chance that it may cache the writes while it's reading from disk, for efficient disk access. You'll need to test to confirm.

[@StephenWagner]

Neuromatiq, I just checked and on the newer versions of DSM, the SSD cache gets attached to the Storage Pool, which should be available to all the volumes inside of that storage pool.

[@medbenmedben]

Thx for the quick answer, I appreciate it 😊 So basicall, I have to unmount the other 3 volumes of different sizes and add them SHR to the default in one single Storage Pool ... That would work ? I assume there is no way to create more than one ssd cache volume in one single nvme ssd drive, that would be great 🙄

[@StephenWagner]

Hi Neuromatiq, no problem! I'm not sure what you mean with your suggested route, or how you have the unit currently configured.

[@medbenmedben]

For the zip extaction, I thought of he cache as a buffer, since the drive is at the same time reading and writing data on itself, it would be great to extract all the data to the cache first then write it 🙄

[@MarcoAboytes]

My only experience with cache is using Intel Rapid Storage Technology. I have a desktop with two HDD in a Raid 1 (2Tb) with a mSATA 32Gb cache disk. When It was set up, the performance was not noticable at first. But with the daily usage, it really feels sometimes that I'm using an SSD disk instead of the Raid 1. The OS performance is beautiful. Perhaps you need to wait some time for the cache to be optimized just like mine. But I could be wrong. Thanks for the video. I didn't know about this Disktations. It seems like a good alternative for network storage.

[@StephenWagner]

Thanks for the comment! :) Yea it's tricky, it all depends on the workloads you're putting the storage through. Typical sequential won't be noticeable, but random loads will. However, I think there will be a part 2 to this video as there's a setting I want to play with to see if it will allow noticeable differences on these types of benchmarks. Stay Tuned!

[@crtzmo]

Hi Stephen, really helpful video -- thank you for the upload! I wonder if you might be able to offer an opinion on two questions related to SYNOLOGY NAS and NVME cache. Grateful for any help you might provide. (1) I am looking at purchasing a DS920+ with either four 8TB or four 16TB Seagate Ironwolf Pro drives, configured as RAID6/10; what is the optimum NVME SSD cache size for either setup, assuming I would purchase two identical M.2 NVME drives? I am looking for a ratio to better understand the ideal environment. (2) Would those two NVME SSD drives be configured as a RAID, and if so, would that function as a "separate" volume from the four Ironwolf drives? Obviously I am new to all of this.. Oh, and, my needs for the NAS -- I am 80% storing a huge digital photography catalog which needs regular access and READ/WRITE functionality, and 20% Time Machine backups from two workstations and some devices. Ok, that was longer than I expected!

[@StephenWagner]

Hey Curtis, sorry for the delay responding... 1) It all depends on the workload and what you're trying to do. Some workloads do not benefit at all from cache, whereas other workloads are drastically improved with NVME cache. 2) When deploying cache, for write cache you need to have 2 NVME and they are configured in a RAID 1 volume. However this is not a user accessible volume. The Synology unit attaches it to the storage as cache. With Synology you can't have NVME user accessible volumes as they are only used for cache.

[@crtzmo]

@@StephenWagner thank you for the feedback, Stephen - really appreciate your time!

[@VirtualTourPhotographer]

Thanks for this. I'm going to be following your very well done step-by-step on prepping NVME cache drives. It's the clearest demo I've seen yet. I'm like a lot of the other users that commented in that my primary goal is improving photo/video editing workflow speeds. With that in mind, I think that possibly going from the native 1Gb/s connectivity to my primary editing computer over to a 10Gb/s connection with a direct connect iSCSI setup could be more important than the NVME upgrade. Once your in a workflow, then data retrieval should be less of an issue as it often gets cached on the local machine. The issue is, just how fast it takes to get from the 1621+ to the editing computer. Thoughts?

[@StephenWagner]

Hi there! I wouldn't recommend using iSCSI for basic file storage. I used iSCSI because I'm using VMware and VMFS with Virtual Machines, which supports clustered access. If you did this with Windows, you wouldn't be able to have multiple systems access iSCSI (it would cause corruption). In your case, I'd definitely recommend using 10Gig, and then use the standard Synology File Share system, as it works great! :) And if you can throw in the SSD/NVME cache, go for that as well as it may help with editing videos if you're doing a lot of HD video editing where it's re-accessing the same file repeatedly.

[@VirtualTourPhotographer]

@@StephenWagner Thanks for the feedback! Good advice. I'll post an update when I get the new gear setup.

[@dougrohde3598]

Did you ever find out why the descrepancies? Why Cache doesn't show big increases?

[@StephenWagner]

Hi Doug, it was due to the workload I was testing with. I ended up fully deploying iSCSI based storage (with NVME cache) for my ESXi environment, and it's lightning fast, crazy fast! I have more info on that here: kzbin.info/www/bejne/j56tq6Gqed-kbNU

[@mathewatm]

Heya. A little bit of a novice, just about to setup this same NAS at home with 4x14tb WD Red Pros in SHR... but big question.. (I seem to be getting conflicting info out there) Does video editing and motion graphics work in after effects benefit from nvme cache?

[@StephenWagner]

Hey Mathew, it's hard to say because I can't say I'm familiar with that type of workload. However if you're constantly opening, editing, and using the same data, repeated access of the same data will benefit from NVME cache. It's designed to cache (and store) data that is constantly accessed. If you have the budget, give it a shot and test it before/after, but I can't give you any definitive answer.

[@dougrohde3598]

Hi Stephen, Here is my benchmark without cache. Why read so BAD? 202 Read - 912 write. Ds1621+ 6 -8tb Iron Wolf Drives Raid 5. Seems terrible. What would be wrong?

[@StephenWagner]

Hi Doug, Can you tell me a bit more about your setup? What connection method are you using, SMB, iSCSI, NFS? Also, what does your NIC configuration look like?

[@dougrohde3598]

The number shown is SMB. with ISCSI, I got same read but 535 write. NIC is 10gb Synology card with Cisco Switch in middle. Thanks for any help.

[@StephenWagner]

Hi Doug, with SMB you are going to take quite a hit on performance. What is your ultimate use case for this? Forgetting about the benchmarking, how do you plan on ultimately using this?

[@dougrohde3598]

@@StephenWagner Storage and 1-2 VM. Why can I not get what you get? I tried to mirror the setup. Why would Reads be so slow?

[@StephenWagner]

It is unusual that your reads are so low. Is you volume still initializing? That could be one cause of performance loss... And while it's not the cause of the extremly low speed, note that your drives are a different class than the ones I used, additionally, I use NVME. SMB Windows shares will cause a performance loss. For your VMs, are you using VMware like my setup? Are you using iSCSI with jumbo frames? Also is jumbo frames enabled on your storage network, as well as your ESXi hosts (if you're using VMware)?

[@mrhobs]

I'm afraid to install the nvme cache I bought. (for up to 6k raw video editing) Seems like its good up to a point, but if your project gets too big, then you hit a bottleneck. Idk, maybe I just made that up, I don't know how this stuff works, so I've been putting off setting up my DS1621+ for over a year...

[@StephenWagner]

Don't be afraid to embrace that NVMe cache goodness.... :) Highly recommend you get your DS1621+ setup, I think you'll love it!

[@antik06]

I haven't really used cache for the last few years (I don't like cache much). But what I do use are M.2 NVMe modules in the NAS for use as a very fast data volume, which Synology can't do, but QNAP can, and thanks to that I run various virtual machines on very fast NVMe (+ I also have a graphics card in my Thunderbolt NAS, so I use this moreover as a powerful PC 😉). For me, I'd like to mention that if anyone is really serious about performance (and the broader uses of a NAS), they should definitely look at a QNAP NAS solution 👍

[@StephenWagner]

I just saw your video on gaming on your NAS, that's super cool! There's a ton of different NAS vendors, all with similar features and their own unique features. I don't think there's any one winner, it all depends on requirements, setup, and also personal preference! :)

[@antik06]

​@@StephenWagner Well, I guess it depends on a point of view. Anyway, I've been through a lot of NAS manufacturers over the years. I used to use Netgear NAS products, then I switched to various Synology NAS models, but it still wasn't the same, there were still quite a few things missing. As a long time apple user I missed the Thunderbolt connectivity, more powerful HW, GPU support, HDMI, 10Gb, and other conveniences (NVMe for data volume ☺). I have to say that QNAP is always, I think... 3-4 years ahead of Synology in terms of development. That's why I eventually switched to QNAP and I don't regret it ✌

[@sumobo7108]

I can't find definitive answer on whether ssd cache benefit photos over google result,like scrolling photos over the phone or desktop.

[@StephenWagner]

Hi sum obo, unfortunately I don't think NVME cache would make much of a difference. The only thing I could see it helping with is possibly thumbnail generation or loading thumbnails, but I don't think it would be a performance increase you'd see using the phone, or possibly even the desktop.

[@MikeBeeTV]

This is another way Synology Fs you. I have a DS1815+ that's died, for a second time. I had an SSD cache on it. I wanted to get my data off of the drives in that NAS but, of course, I couldn't just put the drives into a Linux server and read the RAID array, even though it's claimed that works. I bought a cheap DS423 (non plus mind you) and now my volume is critical because I can't turn off the SSD cache that no longer exists. WTF Synology?! At every point Synology is a fail.

[@vitalii.mikhailenko]

5 TB NAS?) just buy external usb-c ssd

[@StephenWagner]

@@vitalii.mikhailenko Unfortunately cache on this unit cannot be used with USB drives. Also, a minimum of two SSDs are required for write cache.