Why add FPGAs? Data centers have large-scale deployments, so small changes can make measurable differences (think about my example of screws). And energy usage matters. Search logic regularly changes, so ASICs are not viable. The workload does not correspond well to GPUs. This leaves FPGAs as a possible approach to improve efficiency versus CPUs, while still retaining some flexibility.
Why add FPGAs? Data centers have large-scale deployments, so small changes can make measurable differences (think about my example of screws). And energy usage matters. Search logic regularly changes, so ASICs are not viable. The workload does not correspond well to GPUs. This leaves FPGAs as a possible approach to improve efficiency versus CPUs, while still retaining some flexibility.