Re: Improvement of checkpoint IO scheduler for stable transaction responses

In my understanding there's an 'impedance mismatch' between what postgresql wants and what the OS offers.

when it called fsync() Postresql wants a set of buffers selected quickly at checkpoint start time written to disks, but  the OS only offers to write all dirties buffers at fsync time, not exactly the same contract, on a loaded server with checkpoint spreading the difference could be big, worst case checkpoint want 8KB fsync write 1GB.

As a control, there's 150 years of math, up to Maxwell himself, behind t

Adding as little energy (packets) as randomly as possible to a control system you couldn't measure actuators do make a

Didier