DS923+ NVMe cache options

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DS923+ NVMe cache options

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We know by now that only Synology NVMe's work for storage pool, but it seems many are using other brands for read cache, with few if any issues. Is this correct?

Any word on maximum capacity the 923+ can handle? It doesn't appear to be listed in the specifications.

I'm looking at 2 TB NVMe's from several vendors, with pricing not far from Synology's little 400 GB NVMe's, so that seems the way to go, if compatible.

I went with the Seagate FireCuda 530 1TB NVMe, as others had tested it and reported good compatibility. One thing I note, now that I actually have it installed, is there's no power loss protection. I guess this doesn't really matter if used only for read cache, but it probably makes the drive unsuitable for use as read/write cache, which is an option I was evaluating.
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I am starting to venture into the NAS world and have already purchased the DS1522+. Looking to install an NVMe SSD caching/Storage that will work well with this device. For sure will go with a 3rd-party brand for this. So my question what would be the best brand you would recommend? Also does it matter if it is Gen3 or Gen4?
Using the advice in the link I posted in the OP, I went with a single 1 TB Seagate FireCuda 530, based on an initial assumption that I'd be using the cache for read only. I believe (you may want to check me on this) that if used as read only, there is never data that exists solely on the NVMe drive, that it is only a duplicate of data that already exists on your HDD's. If correct, I figured there's no need for dual NVMe's, hence the single larger drive.

However, I've been noticing how often I save some large Excel spreadsheets to the NAS, and the fact that it probably could be quicker with a read/write cache. The problem there is that fresh data may exist solely in the write cache, until later being moved to the HDD's. If setting up my cache for read/write, I'd want to purchase a second NVMe and configure them in RAID-1, for some redundancy of this data.

The other thing I need to check on is power failure protection. The Synology NVMe's have it, and the Seagate FireCudas do not. I am not really sure how important this is, as the NAS is on a UPS, and I thought all drives (not just NVMe's) could go corrupt if experiencing a power failure. So what does "power failure protection" really mean?

At the moment, I'm really trying to figure out how to load and run the Cache Advisor function on my old DSM 6.2 NAS, as that can analyze my historic or current usage pattern and tell me better how to configure the cache on my new NAS. For some reason, Cache Advisor is not appearing on the old NAS, and the help files give no indication why.
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I used 2x Seagate Ironwolf 510's for first 720+ as they WERE LISTED in Synology's Acceptable Hardware List.... And worked fine!

When it came time for second 720+, The Seagate Ironwolf 510's were still on the list, as were but not available-anywhere, Seagate came out with a newer model.... That Model was NOT ON LIST!
So I contacted support.... Asking when new Seagate will be put on list? Support read off a flip card threatening not to support me, etc, etc..... and suggested that if Synology M2's were un-availble, refer again to the list so that I'd not lose my Warranty! So I looked for Samsung Enterprise M.2s.... These were not available either!!! Nor Samsung Mid-range models...
I did find 2x CONSUMER SAMSUNG M.2 that was in list, available, and works, but..... I would have MUCH RATHER WANTED TO USE THE newer SEAGATE Ironwolf !!!

That conversation with Support stuck in my craw and aggravates me-to this day!! Being a retired Component Level Engineer from a TV Netwrok, This approach did not make much sense... components are components.... Afterward, after reading multiple posts here and elsewhere that people were using other 3rd party drives (And I was already using 12-15 year old Barracuda's that were flagged as: "Not in Acceptable Hardware List" in that experimental 720+, as I didn't have $$ for new drives, and these were 'on the shelf' retired from use as Raid 0 array in video editing system for many years!!!) I thought: I KNOW THESE DRIVES ARE GOOD!!!! What the Hell, it's an "Experimental NAS" Let's Experiment!!!! Aftere first nag, nothing since!

So I've tried the following:
3rd Party RAM -- Has Never Prompted as un-acceptable!
3rd Party SATA Drives -- HDD & SSD -- Has Never Prompted as un-acceptable -- after first NAG... Quiet since!
3rd Party eSATA Enclosures --- With 3rd Party SSD inside -- Has Never Prompted as un-acceptable! Never even saw first NAG, like internal drives will!
3rd Party Power Supply --- No issuses whatsoever, and Synology Power Supply is now a spare on the shelf for any of the 3 NAS's we have

By the way, I recently looked at the 'list' and all 3rd party M.2's have been REMOVED! ONLY Synology M.2 remain on the list.... !!!

When the 3rd Party eSATA Enclosure with SSD Worked fine on "experimental" NAS, for 6 months.... They were added to my other two NAS's: 718+ & first 720+.... All 3 with 512MB-2TB SSD's are flawless in operation, and provide inexpensive redundant storage of important files!

I looked into the script file for using M.2's as storage, but seeing that my M2's are not that large, compared to external eSATA, they are better off used as Cache's, though I'm not even certain that as R/W cache's they are speeding things up significantly!
ICBW, but in terms of saving Excel files more rapidly, you would be better served by increased RAM. NVMe cache better serves heavy database activity, where data is constantly hammered thousands of times in short duration. I suggest 16-32 GB memory.
By the way, I recently looked at the 'list' and all 3rd party M.2's have been REMOVED! ONLY Synology M.2 remain on the list.... !!!
There's a half-legit reason for this, but it's a little underhanded, IMO. They removed all 3rd-party M.2's from the list, because now you can use the NVMe's as storage volume(s), and truly only the Synology M.2's can be used for this particular application. However, many 3rd party M.2's will work just fine for cache purpose, and so they should really have just denoted that in their list, rather than removing them due to one application that is only of interest to a fraction of their users.

I think they're just using the storage volume application as a cheap excuse to promote their M.2 drives as the only viable option, but it may force more well-researched users to buy their NAS's from other manufacturers, rather than locking themselves into a Synology-only world.

ICBW, but in terms of saving Excel files more rapidly, you would be better served by increased RAM. NVMe cache better serves heavy database activity, where data is constantly hammered thousands of times in short duration. I suggest 16-32 GB memory.
Only because you said "ICBW", I'd like to hear more on this. I'm game for going read-only on the NVMe, and adding more RAM... except in another thread I was advised to not go 3rd party on the RAM. There's no way in heck I'm paying Synology RAM pricing for 32 GB, they're literally 4x - 8x the cost of all other options.

Overall, I just want to do what's going to be fastest for:

1. Loading large directories of photo thumbnails for browsing/sorting.
2. Opening and saving large excel files with many external references.

I really want to get the Cache Advisor app working in my old DSM 6.2 box, so it can "advise" me based on historical and current usage, but it appears to be missing. The help files on online search turn up zero hits on how to load a missing Cache Advisor, or why it might be missing.
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As a test I shut off, then swapped the R/W caches between 2x 720+’s. One set of R/W M.2’s was twice the size as other set, and tested on speed of access and transfer speeds of small medium large files between either of two 720+’s, To other devices… including a couple Raid 0 arrays, documenting before & after swap, to minimize reporting errors.
I saw no difference in the cache’s size affecting speed, on either 720+. I’d disable cache’s & use script files if the M.2 drives were larger, but aren’t, and cost of 2x large M.2 NVME’s far exceeded cost of eSATA enclosure and spare SATA SSD’s already in the drawer, so…
I don't think you should expect to see any difference in read speed, immediately after installing read cache. Doesn't DSM rely on a pattern of frequent access over time, to determine which content to maintain in the M.2's? If that's not established, then you're probably still just reading off the HDD's. No?

I'd suspect (or hope) the M.2's really shine after you've loaded thumbnails or other meta data from a large photo directory a few times, and DSM then prioritizes storing this content in M.2. This probably takes some time, depending on how they set up the management algorithm.

I haven't read up on how write cache works in DSM, but there I'd expect all incoming content to just port straight to the M.2's. But if a large file is already saved contiguously on the drive, the M.2's may not be noticeably faster than the HDD.
Anyone care to make any bold statements on the importance of power loss protection, in choosing NVMe's for read cache vs. read/write cache?

What is it, really? It's not like our HDD's do well under power loss, if actively writing, etc. And it's also not as if NVMe's suddenly lose stored data when they lose power. So what does this "power loss protection" that Synology is always harping about in their literature even mean?
Thanks. I had done more searching and found basically the same. I keep the NAS on an UPS, but a power cord working loose from the back of the unit, while I'm perhaps hooking up other hardware, is a realistic possibility. So is a NAS power supply failure, we've seen those posted before.

With the M.2's in RAID-1, I suppose that would help prevent corrupting the entire volume if the thing got unplugged during a cache write, but that's really only an assumption.

I have opened and installed one FireCuda 530 1TB NVMe. Not inexpensive, but it won't break the bank either, if I can't return it. I have one other still unopened, that I can easily return. Thinking maybe I should bite the bullet and find some NVMe's with write protection.
Heheh, I don't share the level of backup paranoia that seems to permeate this place. I don't care how much money and effort you throw at the problem, there's always that 'one more' unforeseen catastrophy that wrecks your plans. I have reasonable backups in place and don't worry about the eternal 'what if' scenarios. Best of luck finding your happy place.
We have run Samsung 960's on a 920+ for the last three years without a hitch. They were "on the list". When we added another 920+ the 960's were NLA, so I opted for the 970's. All four of them failed within 3-months. I replaced those with listed WD Red's and in the process became w-a-y more familiar with the inner workings of Synology's "listed drives" than I ever wanted to be straight from the horse's mouth.

Here's the gist of what I recall:
  • Every approved and every failed drive is extensively tested for months in the exact model NAS it is listed for and at the FW level designated in the listing for endurance, responsiveness, reliability, etc., including current flow tolerances at the register levels, etc., etc. It's mind-numbingly exhaustive.
  • Approved drives are approved only at the Brand, Model, and FW level listed. The FW level is considered "squishy" and if your FW level is off but the drive is otherwise approved as to Brand, Model, Type and Capacity, they won't beat you up over it for support.
  • They will support the NAS, even using unapproved drives, but if the drives are not approved they will not provide support for things that directly involve the drives-proper, only those things that are DSM-related, Synology-packages related, and NAS hardware-related, excluding drives.
  • Synology-branded drives have further considerations, to wit:
    • Custom FW for the device
    • Ability to flash the FW from DSM
    • Full support including advance shipped RMA devices
Depending on your situation, I can see the full spectrum from using any old drive to using only Synology branded drives as each use case is different. In our case during the initial setups I was working under severe budget and time constraints. Because our systems are used in active environments, and gratis the Samsung 970 evo's catastrophic failures, I've since been granted budgetary flex and orders all future deployments will carry branded drives.

The "approved list" has it's raison d'être, as do the Synology-branded drives, and it's really quite predictable and predictably mundane. (But it is more fun to infer nefarious intentions!)
I use 2x WD Red SN700 nvme drives in my DS923+.
At the begining one as a volune and the other as read cache. To be honest, after a few months still I couldn't find any serious (noticeable) improvement on my use case so I switched the second drive to storage volume too.
Ours run all-SSD drives, so no benefit in NVMe drives nor cache. It's overkill for our situation as it exists today (Gb LAN's) but brings other benefits in durability, sound levels (v.important for us), and e-consumption.
The "approved list" has it's raison d'être, as do the Synology-branded drives, and it's really quite predictable and predictably mundane. (But it is more fun to infer nefarious intentions!)
Sure. But Synology does not list any third-party options for NVMe drives on the DS923+. As stated previously, there is apparently legitimate reason for this, for cases where the NVMe's are being used as volume(s). But it's also been stated in both Synology and third-party literature that third-party drives can work when NVMe's are used for cache only. They just aren't testing/listing them, anymore.
Been searching, and not really finding any good list out of there for which NVMe M.2's have power loss protection (PLP), versus not. Plenty of compatibility info for NVMe's with various Synology DS's, but PLP is pretty much always ignored in these articles and lists.

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