Can't mount partitions with soft-updates enabled with async option

[Lefteris Tsintjelis]

I am not sure if I do something wrong here or it is suppose to work that
way but the async option doesn't seem to work for partitions that have
soft-updates turned on. Can someone please clarify the difference and if
the speed difference (if any) is significant when using the async option
instead of the soft-updates for cases such as the /usr/obj or as a squid
data storage? Is async preferred over soft-updates when data loss is not
a big issue?

Please CC

Thank you,

Lefteris Tsintjelis
ASDA