[erlang-questions] AMD Ryzen anyone?

[Grzegorz Junka]

On 03/01/2018 08:21, Iblis Lin wrote:
> forgot to CC the list.
>
>
> On 01/03/2018 01:21 PM, Iblis Lin wrote:
>> well, purchasing decision is up to you, but I want to share my personal
>> experience:
>>
>> I will vote -100 for the Ryzen build. For me, the term "Ryzen" means
>> malicious trolling.
>>
>> It wasted my time and mental efforts.
>>
>> I will show you my journal:
>>
>>    - I set up the Ryzen box in 2017/5. Mine is 1700 (8 cores 16 threads).
>>
>>    - I install Arch Linux, ran CouchDB on it... and found the machine
>> crash and reboot regularly in an interval of 2-3 days.
>>
>>    - I also tried to build mainline kernel, (at that moment, it's 4.12
>> IIRC), not work , still crashing or freezing.
>>
>>    - Another test: disabling all deamon, the box can be alive over a week.
>>
>>    - Changing memory module in 2017/6, not work.
>>
>>    - 2017/9 I RMA-ed it.
>>
>>    - After RMA, it still keeps crashing, hard freezing, soft freezing...
>> within 3-6 hr if I run something on it.
>>
>>      the kill-ryzen script DOES kill my box, even it's the new CPU back
>> from RMA.
>>
>>      The *improvement* is the crashing interval shrunk. Thank you AMD.
>>
>>    - 2017/10, I changed my OS from Arch to Ubuntu. not work.
>>
>>
>> On 01/03/2018 06:46 AM, Adam Rutkowski wrote:
>>> Hey all,
>>>
>>> I'm thinking of building a Ryzen machine, mainly for Erlang development. There's this rather obscure bug with some Ryzen processors on Linux/BSD [1] and I'm worried I might be getting a unit from the faulty batch; I have no means of verifying this before purchasing from my local suppliers. I'm wondering if I should I expect any issues with Erlang VM doing the multi-core heavy lifting.
>>>
>>> Cheers
>>>
>>> [1]: https://www.phoronix.com/scan.php?page=news_item&px=Ryzen-Segv-Response
>>>
>>>

Interestingly, it's not that not choosing Ryzen guarantees you a 
worry-free reality:

http://www.dailymail.co.uk/sciencetech/article-5232037/Security-flaw-Intel-chips-past-decade.html

Arguably 50% slowdown or a security flaw is better than a random crash. 
But maybe the real lesson is to choose a processor that doesn't have any 
known vulnerability so far, e.g. Threadripper or a dedicated server 
processor?

GrzegorzJ