64 K write access grouped in a single disk access ?

[chacron1 <eric chacron vz cit alcatel fr>]

Hi Stephen,

I would like to know the behavior of ext3 for a write() request  used
with
O_SYNC
for 64 K in term of disk access method:
- is there a chance to have only one disk access (instead of 16 x 4 K
corresponding to each mapped page ) or at maximum two in journaled mode
?
- if this is possible then how can i force such a grouping of data in a
single disk output ?

NB: i disable cached write at diskdrive level.

regards,
Eric