News for hackers. Stuff that matters.

A comment on Mkfile(8) is severely syscall limited on OS X. Parent comment

Re:Mkfile(8) is severely syscall limited on OS X by cbsmith on Thursday February 16, 2017 @10:31AM (#13660625)
That's not what the article showed. It showed that synchronous IO latency was the limiting factor. By arranging your IOs into little 512-byte chunks, you don't make it terribly easy for the filesystem to efficiently use the underlying device --not surprising, given that it doesn't even want to work in 512 byte sectors, and operates more efficiently with lots of a parallel io operations.
[ Parent | on HN ]
Re:Mkfile(8) is severely syscall limited on OS X by mpweiher on Sunday February 19, 2017 @11:50AM (#13680540)
OS X does write-coalescing.
[ Parent | on HN ]
Re:Mkfile(8) is severely syscall limited on OS X by cbsmith on Sunday February 19, 2017 @03:28PM (#13681800)
You can't write coalesce IO operations that haven't been called yet.
[ Parent | on HN ]