2

I am considering upgrading my workstation (almost a server) with a bootable PCIe drive, the 2TB version of the Samsung 960 Pro. But having a system with PCI v2, SATA II I am not sure if this makes sense as I am afraid of over-saturating the buses.

My main use for my system is data analysis and programming/compilation, where the data is oftentimes XML > 2GB and some of the systems I maintain presently take some 5-10 min to compile. During these tasks I can see that the CPU is doing next to nothing, so I am looking to decrease those times significantly by investing in SSD.

My system (it's from 2010, yes, it's old, but it still outperforms my high-end Asus laptop and I don't quite feel for replacing it yet):

  • Dual Xeon X5680 @3.3GHz
  • 48GB memory
  • RAID-5 physical disks (measured at 150MB/s sequential), 3x 2TB
  • 2TB Data disk (measured at ~250MB/s sequential)
  • Nehalem chipset, Intel 5520 (Tylersburg 35D) with ICH10R I/O controller hub
  • I have three free x16/x8/x4 PCI Express slots, which I think is capable of using that drive (is that a correct assumption?)

My current RAM disk is close to the expected speed of this drive (Read vs write seq. is 3,454MB/sec and 2,157MB/sec) with my current ramdisk (16GB of my 48GB is a RAM disk), I am worried the bus may be the limiting factor and not the raw speed of the drive:

enter image description here

I am particularly worried that my system supports PCIe v2.0 and that this drive requires PCIe v3.0 and this will limit maxing out this drive.

I am essentially looking for upgrading my system such that I get maximum speed gains with disk access. Probably any SSD would already improve things, but if I could get the best money can buy, would it make sense? Is there any sense at all in having such a fast drive in my setup, can use it to its maximum speed?

Small update: this discussion suggests that PCIe v3 is backward compatible with PCIe v2, so the slot should fit. The drive is x4, which I think means the max throughput is 500MB x 4 = 2GB/sec, which is below the maximum of this drive, but only for the (rare) sequential reads.

  • I think the crucial information missing here, is what are you actually doing with that system? Also what's your current storage? It's not like every task is bottlenecked by I/O to begin with. I would go as far and say even in this days most general purpose usage is bottlenecked by single thread CPU performance ... – s1lv3r Jan 20 '17 at 14:23
  • @s1lv3r, you are right, I will update. Basically: data analysis (no gaming etc). Most data files are large (2GB+ XML files), so drive speed is a crucial factor. Also, compilation (one core product takes 10 min compilation and this is in part due to low read/write speeds of phsyical RAID-5 disks). – Abel Jan 20 '17 at 14:28
  • Your sequential drive performance figures will almost certainly be for the outer (and faster) edge of the drives only. I only raise this because it makes the real comparison with normal SATA SSDs that much better - you can find many SATA SSDs that will genuinely sustain 500MB/sec over the whole drive, however your 250MB/sec data disk is going to drop to more like half of that speed by the time you are at the inner edges of the drive. Either PCI-e or SATA SSDs will give you a substantial sequential and random IO boost over your physical drives. – Daniel Lawson Feb 1 '17 at 7:37
1

Storage performance isn't always about throughput. It's about latency. Many people confuse the two.

Even if you can't take advantage of the full throughput available to the card with your PCIe 2.0 slots, you'll benefit greatly from the low latency and random IO performance of the card.

So sure... buy it.

  • Coming from a mechanical disk, even a SATA disk would be immensely faster - no need to buy an expensive pcie disk for such an old system. Moreover, it can have problems booting off pcie. – shodanshok Jan 20 '17 at 14:25
  • Yes, good point. And also @shodanshok. My CrystalDiskMark Seq score on my current physical disk is around 215MB/s, and any upgrade to SSD would likely be sensible. But I am looking for something to make my system "feel good" for another 2-3 years. The dual CPU and memory has been of great help and it still outperforms any other desktop Intel system I have (compilation and data analysis). – Abel Jan 20 '17 at 14:35
  • ewwhite, you can confirm that the M.2 drives fit in a PCIe 2.0 slot, even though Samsung specifies it (for both 960 and other PCIe drives) as v3? – Abel Jan 20 '17 at 14:40
  • @shodanshok, I don't think booting will be a problem (I hope), I have an UEFI BIOS and it can use the EFI boot loader (if I understand the terminologies correctly). I currently have Windows 7 on this system, and several posts suggests I should upgrade to get the best out of NVMe drives. – Abel Jan 20 '17 at 14:52
1

In such an old system, a PCI-express disk will not only be limited in raw speed, but you can have issues booting from it.

So, If you don't have a specific use case for a fast PCI-express disk, I suggest you to buy a much cheaper but well performing SATA disk as Crucial MX300 or Samsung 850 EVO.

  • That is indeed the choice I am unsure about. The MX300 are about 4-6x slower than the 960, but with SATA I am afraid to hit the saturation limit as well. One thought I had was putting three 1TB SSD SATA disks in a RAID-0 configuration, but I estimate that the bandwidth of the RAID controller won't cut it. – Abel Jan 20 '17 at 14:32

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.