It appears that my Time Machine backups over Gigabit ethernet are bottle-necked at the 2TB HD in my 802.11ac Time Capsule, at ~20MB/s (the HD write rate being ~160MB/s).
When researching whether there would be any benefit from replacing the HD with an SSD, I found that the few threads on the subject said an SSD would be a waste, arguing that the SATA III HD interface in the Time Capsule is already a 6 Gb/s interface -- but it seems to me that the SATA III interface isn't limiting, because 6Gb/s (750MB/s) is still quite a bit above the ~450-550 MB/s rates of today's SSDs.
In other words, it looks like SSDs would give me somewhere between 2-3 times the Time Machine back up rates of the stock HD (40-50 MB/s vs. 20MB/s over ethernet).
So (other than the obvious cost issues), what am I missing that would result in my Time Machine backups not benefitting from installing an SSD in the Time Capsule?
When researching whether there would be any benefit from replacing the HD with an SSD, I found that the few threads on the subject said an SSD would be a waste, arguing that the SATA III HD interface in the Time Capsule is already a 6 Gb/s interface -- but it seems to me that the SATA III interface isn't limiting, because 6Gb/s (750MB/s) is still quite a bit above the ~450-550 MB/s rates of today's SSDs.
In other words, it looks like SSDs would give me somewhere between 2-3 times the Time Machine back up rates of the stock HD (40-50 MB/s vs. 20MB/s over ethernet).
So (other than the obvious cost issues), what am I missing that would result in my Time Machine backups not benefitting from installing an SSD in the Time Capsule?