Mkfile(8) is severely syscall limited on OS X

Re:Mkfile(8) is severely syscall limited on OS X by Matt3o12_ on Sunday February 12, 2017 @07:27AM (#13628043)

This still begs the question I've had since day one when learning about buffers: what the heck is the recommended buffer size. I've seen a lot of old code that use extremely small buffer size as well as some recent code that use extremely high buffer sizes (up to 10MB).

What is a good sweet spot that runs well on older hardware (less then 10 years old) and new hardware? And should network buffers be bigger or smaller then disk buffers?

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Re:Mkfile(8) is severely syscall limited on OS X by throwawayish on Sunday February 12, 2017 @07:57AM (#13628122)

Network buffers are a completely different animal, also harder to optimize...

Disk IO buffers, it's easy nowadays, just use something like a MB, which is just fine for almost any application, and doesn't stack up to much memory use (unless you're writing many files concurrently, which can bring it's own problems as well)

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Re:Mkfile(8) is severely syscall limited on OS X by yjftsjthsd-h on Sunday February 12, 2017 @09:07AM (#13628345)

That actually does sound about right, but do you know how to derive that? I'm curious how to figure it out.

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Re:Mkfile(8) is severely syscall limited on OS X by RyanZAG on Sunday February 12, 2017 @08:51AM (#13628291)

Judging by the post here, 512kb buffers seems like a good bet?

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Re:Mkfile(8) is severely syscall limited on OS X by mpweiher on Sunday February 12, 2017 @10:14AM (#13628671)

For a an SSD with 2GB/s throughput and the syscall overhead of OS X: yes. Go higher if you want some headroom for the next generation of faster SSDs.

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Re:Mkfile(8) is severely syscall limited on OS X by gens on Sunday February 12, 2017 @10:18AM (#13628700)

Just do a test with dd or some small piece of code. Why rely on heresay.

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