Any way to collect historical data for NVRAM stats?

Hi,

ONTAP 9.1RC1

AFF8040 HA

We have a Linux sever running SAS software and NFS mounts to the AFF for SAS data access. SAS software is heavy on sequential writes. I'd like to find out whether NVRAM keeps getting full when there is large amount of sequential writes thus gets flushed to SSDs so frequently that it acutally becomes a bottleneck. I can do ssysstat to get some NVRAM related realtime stats but is there a way to retrive historical data for such NVRAM stats? I don't see it's possible in Unified Manager.

Thanks,