Heh, no 4K numbers in that CDM screen shot. Would rather see more progress in that regard than faster sequential numbers. But I guess if the mark up of PCIe 4.0 NVME drives isn't too high, I will get one for my next system drive and the 960 Evo I have will become my data drive. Fun stuff.
Every website I frequent uses 4k testing and none have 64k testing. A quick Google also showed nothing pertaining to your statement that 4k is irrelevant for consumer workloads. And I don't know why you have to mention that 4k is not being limited by the PCIe interface, since I never said or alluded to that being the case.
4k random writes are relevant for consumer workloads, because that affects swap performance. 4k random reads are only relevant on consumer operating systems that implement swap partitions, like Linux, MacOS, and BSDs. Windows uses page files. WIndows does 128k reads to optimise throughput, so 4k random read IOPS are not as relevant for Windows users as a result. Even on Linux, MacOS, and BSDs filesystem reads are 128k unless you configure them otherwise, so unless you're going to swap 4k random reads are also irrelevant... even for enterprise workloads.
I guess I should add that your 4k random read performance on any OS that has filesystem reads configured to 128k read-ahead will be limited to 1/32 of the ideal throughput, simply because 31/32 of the data is going into the VFS buffer and then getting discarded. :-( If you really care about your 4K random read performance, you *must* disable read-ahead.
That might affect file contents, but I don't think most operating systems perform sequential readahead when walking file system structures while trying to find where the file contents are. And when the file is less than 128kB long, I don't think the readahead continues past the end of the file.
But it really hasn't shown any improvement in consumer workload. Optane had much better 4K Random, but it hasn't shown any benefits when compares to fastest consumer SSD. Which leads me to believe Seq Read Write is still one of the most important aspect.
If you ask anyone that used proper optane drive as boot drive [even the dual channel 58gb/118gb versions] they will tell you that its same feeling going from SSD to optane like from HDD to SSD. Everything is more snappy, programs load faster, even heavy programs like say my Waterfox with 5000+ TABS that loads for 30 second [maybe 40] on SATA SSD, loads almost instantly on optane 900p
4K random does matter for database use - and there are a surprising number of databases on Windows now, hiding in the background. However, the difference may not be significant for the desktop level of usage.
I suggest you take a look at our statistics for the IO size breakdown of the ATSB tests. All three have 4kB IOs as 25-30% of all IOs. These are recordings of real-world consumer application usage, and 4kB IO performance is obviously a significant factor.
Anton, interesting note AMD also paid 15 Million to push the timeline up on the development cycle so drives based on this controller could launch at the same time. This was a brilliant move imho.
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Death666Angel - Friday, May 31, 2019 - link
Heh, no 4K numbers in that CDM screen shot. Would rather see more progress in that regard than faster sequential numbers. But I guess if the mark up of PCIe 4.0 NVME drives isn't too high, I will get one for my next system drive and the 960 Evo I have will become my data drive. Fun stuff.ktmrc8 - Friday, May 31, 2019 - link
62.31 MB/s from this CDM screen shot for Q1T1 random 4K read. Article also has RAID 0 stats.https://pc.watch.impress.co.jp/docs/news/event/118...
peevee - Friday, May 31, 2019 - link
4K is not limited by PCIe interface, and anyway irrelevant for consumer workloads. Random 64K would be better today.Death666Angel - Friday, May 31, 2019 - link
Every website I frequent uses 4k testing and none have 64k testing. A quick Google also showed nothing pertaining to your statement that 4k is irrelevant for consumer workloads. And I don't know why you have to mention that 4k is not being limited by the PCIe interface, since I never said or alluded to that being the case.linuxgeex - Friday, May 31, 2019 - link
4k random writes are relevant for consumer workloads, because that affects swap performance. 4k random reads are only relevant on consumer operating systems that implement swap partitions, like Linux, MacOS, and BSDs. Windows uses page files. WIndows does 128k reads to optimise throughput, so 4k random read IOPS are not as relevant for Windows users as a result. Even on Linux, MacOS, and BSDs filesystem reads are 128k unless you configure them otherwise, so unless you're going to swap 4k random reads are also irrelevant... even for enterprise workloads.linuxgeex - Friday, May 31, 2019 - link
I guess I should add that your 4k random read performance on any OS that has filesystem reads configured to 128k read-ahead will be limited to 1/32 of the ideal throughput, simply because 31/32 of the data is going into the VFS buffer and then getting discarded. :-( If you really care about your 4K random read performance, you *must* disable read-ahead.Billy Tallis - Friday, May 31, 2019 - link
That might affect file contents, but I don't think most operating systems perform sequential readahead when walking file system structures while trying to find where the file contents are. And when the file is less than 128kB long, I don't think the readahead continues past the end of the file.ksec - Saturday, June 1, 2019 - link
But it really hasn't shown any improvement in consumer workload. Optane had much better 4K Random, but it hasn't shown any benefits when compares to fastest consumer SSD. Which leads me to believe Seq Read Write is still one of the most important aspect.Mr.Vegas - Friday, September 6, 2019 - link
If you ask anyone that used proper optane drive as boot drive [even the dual channel 58gb/118gb versions] they will tell you that its same feeling going from SSD to optane like from HDD to SSD.Everything is more snappy, programs load faster, even heavy programs like say my Waterfox with 5000+ TABS that loads for 30 second [maybe 40] on SATA SSD, loads almost instantly on optane 900p
GreenReaper - Monday, July 1, 2019 - link
4K random does matter for database use - and there are a surprising number of databases on Windows now, hiding in the background. However, the difference may not be significant for the desktop level of usage.Billy Tallis - Friday, May 31, 2019 - link
I suggest you take a look at our statistics for the IO size breakdown of the ATSB tests. All three have 4kB IOs as 25-30% of all IOs. These are recordings of real-world consumer application usage, and 4kB IO performance is obviously a significant factor.FreckledTrout - Monday, June 3, 2019 - link
Anton, interesting note AMD also paid 15 Million to push the timeline up on the development cycle so drives based on this controller could launch at the same time. This was a brilliant move imho.