Comment by fmajid

Back when we used something called the DDRdrive X1 as the ZFS ZIL drive (essentially a write log) on our high-performance database machines. It's a PCIe card with 4GB of RAM, 4GB of SLC flash and a supercap so that in the event of a power failure the RAM is written out to flash.

https://ddrdrive.com/menu1.html