[linux-lvm] writeback cache not promoting writes

[Linda A. Walsh]

Max Power wrote:
>> # dd if=/dev/zero of=/dev/mapper/BigData-data \
>> #    bs=1G count=1 oflag=direct
>>     
----
    I don't know how it interacts in the case you have setup, but
oflag=direct usually has 'dd' writing to the physical device -- not any 
system
cache.  I don't know if lvm's cache changes that behavior, but you might
try it w/o the direct flag?