Re: test_fsync open_sync test

Bruce Momjian wrote:
> Is there a value to this test_fsync test?
>
>     Compare open_sync with different sizes:
>     (This is designed to compare the cost of one large
>     sync'ed write and two smaller sync'ed writes.)
>             open_sync 16k write               242.563 ops/sec
>             2 open_sync 8k writes             752.752 ops/sec
>
> It compares the cost of doing larger vs. two smaller open_sync writes.
>   

Might be some value for determining things like what the optimal WAL 
block size to use is.  All these tests are kind of hard to use 
effectively still, I'm not sure if it's time to start trimming tests yet 
until we've made more progress on interpreting results first.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
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