Niall’s virtual diary archives – Tuesday 19th March 2019

Tuesday 19th March 2019: 4.36pm. You may remember that I pulled the trigger on a new workstation to replace my six year old Ivy Bridge one:

- Sixteen core AMD Threadripper 2950x @ 3.5Ghz, turbo 4.5Ghz.
- 32Gb of DDR4-3200 RAM @ 64Gb/sec 75Gb/sec.
- 512Gb Samsung 970 Pro NVMe SSD @ 3.1Gb/sec

I spent no less than thirteen - yes, thirteen - hours yesterday during the public holiday pulling out the old system, and putting in the new. Went home after midnight with, finally, a machine booting into Windows, after a very long and frustrating day which included having to cut through sheet metal in the case to make space for my video card, and slicing my wrist on sharp metal. Yay.

Spent most of today installing stuff and trying to get Maystreet's code building again, as after all today is a work day. Just got the Windows build working there, currently working on the Linux build.

So, first impressions of the new platform is how little different it feels to the preceding one. Which is the first time that's ever happened to me in an upgrade! Yes it feels slightly snappier. But it's a "fresh Windows install" kind of slightly snappier, not a "I just dropped over a grand on a new workstation" snappier. Much of the cause is that the preceding Ivy Bridge system also ran at 3.9Ghz, and also had a top end Samsung SSD, albeit SATA instead of NVMe connected. But despite all these oodles of CPU cores and 4x the memory bandwidth, it makes very little difference indeed to perceived latency, for the simple reason that the old system responded in pretty much the same lag as this new one does.

However where you notice the difference big style is compiling Maystreet's code. That used to take a number of hours to compile it all, and a good twenty minutes for a complete rebuild of the subproject I'm working on. This new system does considerably better, it's under five minutes now. Which will be a big productivity bump in the months to come.

Something interesting is that even the ninja build tool rarely keeps more than eight CPU cores busy for long. Occasionally it hits sixteen cores, but it doesn't last long. The build here just isn't parallelisable enough to do better.

In terms of other observations of the new workstation, apart from how awful it was to get it booting at all, since I figured that out it's been boringly predictable. The last time I had an AMD system was over a decade ago, and the chipset drivers just weren't quite as stable nor polished as the Intel ones. So far - albeit it's been just a day - I've seen zero issues. It's been very smooth running, all the hardware has been compatible, everything has benchmarked at speeds you'd expect first time (note my RAM bandwidth is a good bit more than what online suggested, I am running this system in its true NUMA configuration instead of the hardware trying to hide that not all the RAM is equally close to all of the CPU cores). In short, once it actually booted, it's been very plain sailing indeed.

Now just need to find the time to put the old parts onto eBay!