CHR <-> RB750Gr3 via GRE over IPSEC Performance issue

I’m running CHR on Intel Haswell, without TSX, to support high availability failover to Intel Xeon CPU E5-2640v3. I’ve confirmed AES pass through by booting the CHR guest using CentOS 7 recovery environment.

Confirming ‘aes’ instruction availability:
grep -m1 -o aes /proc/cpuinfo

We obtain the following benchmarks in the VM:
openssl speed -evp aes-128-cbc

type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes                     
aes-128-cbc     511101.85k   547731.20k   555776.60k   560752.67k   558724.44k

openssl speed -evp aes-256-cbc

type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes                     
aes-256-cbc     371521.68k   394245.03k   401446.36k   399955.91k   402183.22k

Directly on slowest hardware:
openssl speed -evp aes-128-cbc

type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes                     
aes-128-cbc     541865.83k   585278.50k   595671.30k   602248.53k   603339.43k

openssl speed -evp aes-256-cbc

type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes                     
aes-256-cbc     398849.01k   423887.98k   430012.84k   431852.89k   432622.25k

That equates to 5.2 Gbps, when using AES 128 bit CBC encoding within the virtual guest. I don’t see L2TP IPSec in CHR reporting ‘Hardware AEAD’ when reviewing the installed SAs either…