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WD SN850 delivers the best performing SSD we've tested

tweaktown.com

21–30 of 62 posts

Re: WD SN850 delivers the best performing SSD we've tested

#21
post #9

I've heard that SATA and NVME SSDs have similar performance for use cases such as lightweight app usage and loading games. Does anyone know what the typical use cases are for these high performance drives?

The reason is it takes time to reach those top speeds for each individual file. So if you're dealing with many small files it's difficult to reach and sustain the max speed. If you're working with big files like editing 4k or 8k video footage that's when you really get the full benefits

Re: WD SN850 delivers the best performing SSD we've tested

#22
post #11

Maybe I haven't been paying attention, but I've never had a site attach extra text to copied text like this site does. I wanted to see what the test machine's case looks like, so I copied the make and model and pasted it into a search bar, and got "Read more:" and a link to the page along with the text I wanted to copy. No thanks. I'll be skipping that site in the future, unless that javascript comes from a place I c…

You can probably just block JavaScript entirely for a site like this. I doubt it depends on it. But I agree that adding text to copied text is really irritating.

Re: WD SN850 delivers the best performing SSD we've tested

#23

> importantly, for all SSDs, disable write-cache buffer flushing for best performance. Is this actually good advice, especially without mentioning the durability risks?

The biggest players in the game do not use SSDs for persistent storage longer than x weeks. It is offloaded to tape at some point and restored periodically.

I'm also curious as to whether this is true. From what I understand and can gather from tech talks from large firms, it is common (up to and beyond petabyte scale) to use ceph clusters purely consisting of SSDs and HDDs (no tape) to store mission critical data, with cache tiering used to balance hot and cold data. AFAIK, because of their self-healing nature thanks to replication/erasure coding algorithms, all that needs to be done is replace corrupted drives periodically, thus making tape drives non-essential unless periodic full backups are required for off-site storage. Please feel free to correct me if I'm wrong in any of this. Thanks.

Re: WD SN850 delivers the best performing SSD we've tested

#24

Those speeds look nice. 7100srMB/s and 5250 srMB/s I ended up getting a Samsung Evo 970 plus (1TB) a while ago because it was in a sale for $85. Almost half the speed of the ones in the benchmark. Maybe I should have waited.

> Almost half the speed

And 1/3 the price. If you bought it because it was on sale, doesn't that mean you're at least somewhat price sensitive? I don't think you should feel bad about your purchase.

Re: WD SN850 delivers the best performing SSD we've tested

#25
post #9

I've heard that SATA and NVME SSDs have similar performance for use cases such as lightweight app usage and loading games. Does anyone know what the typical use cases are for these high performance drives?

The reason is it takes time to reach those top speeds for each individual file. So if you're dealing with many small files it's difficult to reach and sustain the max speed. If you're working with big files like editing 4k or 8k video footage that's when you really get the full benefits

It really depends on your filesystem for this. However, the latency should be comparable across technologies, proportionately taking a bigger chunk of transfer times for small files.

Re: WD SN850 delivers the best performing SSD we've tested

#27

Earlier quoted context omitted.

Dont most SSDs have capacitors for this?

Only enterprise class drives typically have power loss protection and even that isn't a guarantee as some in that class don't have PLP.

As far as I'm aware, server SSDs without PLP are a relatively recent trend, and most of the examples I'm aware of are entry-level SATA drives. A few companies are also marketing their client/consumer M.2 NVMe drives for use as server boot drives, but at least one competitor in that segment has made a purpose-built low capacity NVMe drive with PLP.

Re: WD SN850 delivers the best performing SSD we've tested

#28
post #23

Earlier quoted context omitted.

The biggest players in the game do not use SSDs for persistent storage longer than x weeks. It is offloaded to tape at some point and restored periodically.

I'm also curious as to whether this is true. From what I understand and can gather from tech talks from large firms, it is common (up to and beyond petabyte scale) to use ceph clusters purely consisting of SSDs and HDDs (no tape) to store mission critical data, with cache tiering used to balance hot and cold data. AFAIK, because of their self-healing nature thanks to replication/erasure coding algorithms, all that ne…

>to use ceph clusters purely

Exactly! Use ceph so you don't have to care about burning ssd/hdd/server/switch/racks/dc, you have your object-storeage, FS, block-device, with one service and that's it.

Re: WD SN850 delivers the best performing SSD we've tested

#29
post #4

> importantly, for all SSDs, disable write-cache buffer flushing for best performance. Is this actually good advice, especially without mentioning the durability risks?

StackOverflow answer here: https://superuser.com/a/1215634 It's essentially the typical "without this enabled, you will lose data in case of power loss, potentially breaking the O/S".

It's a tangent, but I only recently realized/considered that UPS batteries had come along for the ride with lithium-ion.

I bought one that should power my internet+wifi for about an hour for $45.

I guess even a small one like that would handle power blips for a home server, but in an outage the battery would quickly run out and the setting would matter.

Re: WD SN850 delivers the best performing SSD we've tested

#30
post #4

> importantly, for all SSDs, disable write-cache buffer flushing for best performance. Is this actually good advice, especially without mentioning the durability risks?

StackOverflow answer here: https://superuser.com/a/1215634 It's essentially the typical "without this enabled, you will lose data in case of power loss, potentially breaking the O/S".

One important point that the StackOverflow answers miss is that the Windows checkbox for buffer flushing has a different meaning for SATA SSDs than for NVMe SSDs. If you want a reasonably fair synthetic benchmark to compare NVMe SSDs against SATA SSDs while bypassing any caching the OS is doing with main system RAM, you pretty much have to toggle that switch for at least NVMe drives. Or use Linux, which has actual documentation for its NVMe driver, and the source code is available where that falls short.
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