@Ben interesting, I did something similar and also ended up with a 64KB buffer (seemed like the default of 4KB didn't work very well in my context). How did you decide of the buffer size?
Also, there is something that I don't understand. The default buffer size works really well for a toy example (like the one I posted in my original question), but the improvements are much less dramatic in my program, for the same pattern of writing to stdout. I can't work out a reason for this yet. On Sunday, 20 December 2020 at 20:31:52 UTC ben...@gmail.com wrote: > And os.Stdout (and friends) are all regular *os.File objects (which as Jan > said, don't buffer). It was non-intuitive to me that stdout didn't buffer > by default, because it's such a bad thing for efficiently writing lots of > output, but I guess it makes sense when you want terminal output to appear > right away. So I realized it made sense, and gives you more control. And > it's so easy to wrap it in a bufio.NewWriter() ... Flush() if you need > buffering. > > I ran into this exact same issue when implementing GoAWK ... a 10-line fix > gave me a 10x speedup. > https://github.com/benhoyt/goawk/commit/60745c3503ba3d99297816f5c7b5364a08ec47ab > > -Ben > > On Monday, December 21, 2020 at 12:27:43 AM UTC+13 arn...@gmail.com wrote: > >> Ah, that is it, thank you! >> >> On Sunday, 20 December 2020 at 11:06:05 UTC Jan Mercl wrote: >> >>> On Sun, Dec 20, 2020 at 11:53 AM Arnaud Delobelle <arn...@gmail.com> >>> wrote: >>> >>> > TLDR; a simple test program appears to show that Go's (*os.File).Write >>> is 10x slower than C's fputs (on MacOS). >>> >>> Apples and oranges. fputs buffers, os.File does not. Rewrite the >>> benchmark using bufio. >>> >> -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/30bc991b-1a94-4ce7-bc0d-fea10777b233n%40googlegroups.com.
