java.nio.*Buffer read/write atomicity

Ulf Zibis Ulf.Zibis at
Thu Dec 20 17:49:34 UTC 2012

Am 20.12.2012 18:18, schrieb Aleksey Shipilev:
> On 12/20/2012 09:11 PM, mark.reinhold at wrote:
>> 2012/12/19 12:37 -0800, david.holmes at
>>> If multiple threads have to synchronize access to the buffer then the
>>> reads/writes do not need to be atomic. Atomicity is only needed when
>>> data races are allowed.
>> Correct.
>> Byte buffers, especially the direct variety, are all about performance.
>> Making operations upon them atomic is not a problem that needs to be
>> solved.
> I would say that you can have the read/write atomicity for heap
> ByteBuffers without the compromises in performance (i.e. like direct
> ByteBuffer does with full-width reads/writes) -- basically prune out the
> Java code which breaks ints into the series of bytes, and cram in
> Unsafe.putInt() against backing array.

I believe, it would enhance performance too.
Also intrinsifying could be interesting.
Here is a similar request:


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