Binary compatibility of KNL coprocessors

[Owen_J_]

We are currently trying to decide on the layout of our new HPC system (to replace the old one based on twin Haswell processors + 6 KNC cards). The cheapest option would be to buy 6 KNL PCIe cards, but given my experience trying to port software to the KNC cards (I've been battling with OpenFOAM and associated 3rd party libraries for the last couple of weeks, and still not got it to compile for the MICs) I'm extremely wary of these coprocessors.

Apparently the KNL socketed processors are binary-compatible with standard Xeon processors, but does the same apply to the KNL coprocessors?

There's a real dearth of information online about the KNL coprocessors. If compiling native applications for these new cards is as difficult as it was for the KNC cards, we'll probably just get 4 KNL socketed processors instead.

Thanks in advance to anyone who can shed some light on the matter!

[TimP]

https://software.intel.com/en-us/forums/intel-many-integrated-core/topic/737882 appears to cast doubt on the intent to support the coprocessor version of KNL.

[JJK]

I agree with Tim P: it appears uncertain whether the KNL coprocessor version is still available. You can still buy them online, however, for roughly USD 4000 a piece - that is actually more expensive than buying a new KNL server from scratch. Plus, with a KNL CPU you are no longer hindered by the PCIe bottleneck when accessing main memory; for computational problems requiring large amounts of RAM (well above 16 GB) this can be a real issue.
 

[Owen_J_]

JJK wrote:
 

You can still buy them online, however, for roughly USD 4000 a piece - that is actually more expensive than buying a new KNL server from scratch.

We managed to source them for more like $2100 apiece, which makes them slightly more reasonable. Still not worth the operational risk of finding out that we can't compile the necessary software for them and having to find buyers to sell them on, so we've chosen to go with the socketed processors instead.