Use ThreadLocalRandom instead of Math.random() #11165
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chrisvest
reviewed
Apr 17, 2021
| @@ -178,7 +179,7 @@ protected void encode(ChannelHandlerContext ctx, WebSocketFrame msg, List<Object | |||
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| // Write payload | |||
| if (maskPayload) { | |||
| int random = (int) (Math.random() * Integer.MAX_VALUE); | |||
| int random = PlatformDependent.threadLocalRandom().nextInt(); | |||
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This was previously never negative but now it can be. That won't be a problem, right?
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From what I know it's not a problem. But that's a good point. Who knows, maybe someone already expects it to be positive :). So let's preserve the prev behavior just in case.
chrisvest
approved these changes
Apr 18, 2021
normanmaurer
approved these changes
Apr 19, 2021
chrisvest
pushed a commit
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Apr 19, 2021
Motivation: `ThreadLocalRandom` doesn't cause contention. Also `nextInt()` generates only 4 random bytes while `Math.random()` generates 8 bytes. Modification: Replaced `(int) Math.random()` with `PlatformDependent.threadLocalRandom().nextInt()` Result: No possible contention when random numbers for WebSockets.
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@doom369 Thanks! |
raidyue
pushed a commit
to raidyue/netty
that referenced
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Jul 8, 2022
Motivation: `ThreadLocalRandom` doesn't cause contention. Also `nextInt()` generates only 4 random bytes while `Math.random()` generates 8 bytes. Modification: Replaced `(int) Math.random()` with `PlatformDependent.threadLocalRandom().nextInt()` Result: No possible contention when random numbers for WebSockets.
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Motivation:
ThreadLocalRandom doesn't cause contention. Also
nextInt()generates only 4 random bytes while Math.random() generates 8 bytes.Modification:
Replaced
(int) Math.random()withPlatformDependent.threadLocalRandom().nextInt()Result:
No possible contention when random numbers for WebSockets.