Re: should frontend tools use syncfs() ?

I ran a couple of tests for pg_upgrade with 100k tables (created using the
script here [0]) in order to demonstrate the potential benefits of this
patch.

pg_upgrade --sync-method fsync
    real    5m50.072s
    user    0m10.606s
    sys     0m40.298s

pg_upgrade --sync-method syncfs
    real    3m44.096s
    user    0m8.906s
    sys     0m26.398s

pg_upgrade --no-sync
    real    3m27.697s
    user    0m9.056s
    sys     0m26.605s

[0] https://postgr.es/m/3612876.1689443232%40sss.pgh.pa.us

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com