Let IO#sync only affect writes, introduce IO#read_buffering? and use it in urandom
#6304
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RX14
approved these changes
Jun 30, 2018
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By the way, to review this you can see 4e0dc9e. It's more or less the same code, except that when using |
ysbaddaden
approved these changes
Jul 1, 2018
sdogruyol
approved these changes
Jul 1, 2018
|
As this PR fixes serious perf regression IMO it should go into |
jgaskins
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to jgaskins/crystal
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Apr 6, 2022
This doesn't actually set read buffering anymore since crystal-lang#6304
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Fixes #6303
Being able to disable read buffering for
IO::Bufferedis good. However, havingsyncaffect both reads and writes makes it easier to enable just buffering for one direction: for sockets it's better to not have write buffering by default, so whatever you write goes directly to the socket (you can always setsync = falseand manually flush, which is what we do in a few places), but reads should always be buffered for performance reasons.With this PR we could release 0.25.2 as a bugfix release for this performance regression.
Then for 0.26.0 we could rename
synctowrite_buffering, or just leave it assync. Maybewrite_bufferingis more explicit, even though it's a breaking change. But then, disabling read buffering is a very uncommon use case (urandom... what else?), so maybe havingsyncandread_bufferingas separate, asymmetric properties isn't that bad.(I know I could have used
getterorsetterfor this, but given thatsyncdoesn't use them I decided to follow that style. If someone wants to do a follow up PR to "improve" that (it's not really an improvement, because macros are slower to compile and it's just one/two line differences), then please go ahead).