I’ve just upgraded my DS1621+ with a Samsung 990PRO m2 NVME SSD and I’m struggling to notice any tangible benefit as of yet.
I am running Mac Studio M1 max with Sonoma 14.7. It has 10gbe networking to an upgraded 10gbe Synology pcie card in the back of the 1621+ via a cat 6a cable, and I currently have 4 of the 6 bays populated with Ironwolf HDDs. Regular tests with black magic disc speed test give me 550mb/s write and 440 mb/s read.
I work in post production in the film industry so heavy codecs (R3D, Arriraw, ProRes4444XQ etc) in UHD - 8K and real time playback when scrubbing through timelines is an absolute necessity.
I thought that adding an SSD in one of the m2 nvme bays as read only cache would noticeably speed up performance and playback, but I’m struggling to see anything tangible.
The test I have ran so far was to time how long it took to pull off an 80gb file from my NAS to my mac desktop, and then repeat the process (assuming that it would cache the first time round and be “hot” the second time, so therefore would be faster). Nothing noticeable, so I checked within activity monitor to see what speeds I achieved on a separate 50gb file the first and second attempt and they were both about 350 - 380mb/s - but was hoping once it was “hot” int the cache it would be lightning fast.
Unsure what I’m missing here. Obviously the Samsung 990PRO gives you a warning that this is not on the list of Synology compatible devices, but Will at SpaceRex was recommending these very drives for SSD caching recently, so I’m sure they should work fine.
Please let me know if you need more information, and I thank you massively in advance of any help / guidance you’re able to give.
First, did you configure the cache in Storage Manager and assign it to the volume you use (you might have one volume)? Just checking.
That assumption is made more often but not always sufficiently backed by data. Long story short, an SSD cache can improve performance in certain situations, like many small files accessed frequently and virtual machines. However, more often than not, it does not make a difference.
There is a tool in Storage Manager, the SSD Cache Advisor, that is useful before you buy and install a cache. You can look at how it is used now in Storage Manager.
Hi Paul, thanks for getting bacl to me - yes, all set up in the DSM interface and assigned to my one storage volume. I can see it in Storage Manager, which is reassuring, but no noticeable gains as of yet.
FWIW I get the same with Blackmagic but if I use ATTO here is a chart I get. I have no idea if it’s faster than before since I had the SSD from the start. This may all be the 10GB aspect.
This is a brief note for those interested. Pinning Btrfs metadata to the SSD cache is a read-write cache ability for which you need (at least) two SSD drives. As discussed here, the read-only cache with one SSD drive does not have this option.
SSD cache do not cache big files. Previously there was option to on/off this behavior. Now option is not available and Synology just not cache big files - I don’t remember exact value but it should be mentioned somewhere in documentation.
