Of course, with sync writes on the performance is also truly horrible and the device is practically unusable.
I am eating the consequences of the many bizarre decisions NTGR have taken during the last few years (essentially destroying the potential of capable hardware with horrible software decisions) and will be copying all data off the device, downgrade to OS4 (or fashion some way of forcing Debian on it), and never again buy or recommend a Netgear product in my life.
This ends a 20 year+ old relationship, back to the time where "Bay Networks" was on Netgear products. Good work lads.
