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Questions tagged [direct-buffer]

In Java, direct buffer is usually used with channels and native I/O routines. It's out of JVM heap and gc operation. It's more expensive to create than non-direct buffer, and better create for large and long-live buffer. The io operation could be better on direct buffer than non-direct buffer, though it's platform and jvm implementation dependent.

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Java - When does direct buffer released?

Since it's out of jvm heap & gc, when does it released? Or, it remain until process termination? I already checked: how to garbage collect a direct buffer java Deallocating Direct Buffer Native Memory in Java for JOGL ByteBuffer.allocate() vs.…
Eric
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cannot access a member of class java.nio.DirectByteBuffer (in module java.base) with modifiers "public"

Got a project which is built to still support Java 6. The code below is inside a jar file built with Compiler compliance level 1.6 That jar file should be called from java apps built for java 6 or newer. It runs fine in Java 8 as well. Now with…
datafiddler
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Direct Buffer used by ByteBuf is not fully released

I am using Netty 4.1.17-Final with Direct Buffer. We send and receive 100 MB of byte[] in the test program, and when decoder reaches 100 MB, we discard it without doing anything. @Override public void decode(ByteBuffer _in, List _out) { …
nikai
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Releasing a direct buffer in java and possible pitfalls

we have the following piece of code: long buffer = ((DirectBuffer) ByteBuffer.allocateDirect(256)).address(); It seems that there is no reference to direct buffer (as an object) on the thread's stack. So, it means that that object is…
Gilgamesz
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Java direct ByteBuffer - decode the characters

I would like to read the bytes into the direct ByteBuffer and then decode them without rewrapping the original buffer into the byte[] array to minimize memory allocations. Hence I'd like to avoid using StandardCharsets.UTF_8.decode() as it…
David Siro
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Reuse the same IntBuffer object to wrap a different Bytebuffer

I need to get a view of a ByteBuffer b using the same object IntBuffer viewBuffer without having to instantiate a new object every time the reference to the ByteBuffer changes. // An external ByteBuffer ByteBuffer b1 = ByteBuffer.allocateDirect(1024…
PhiloJunkie
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How to release Pooled direct ByteBuf in netty when written after by ChannelHandlerContext?

In my c/s project, c/s need to exchange fixed-size message with netty. I use pooled direct buffer to buffer message. Code just like below: public void channelRead(ChannelHandlerContext ctx, Object msg) { ByteBuf in = (ByteBuf) msg; try { …
shanfeng
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jconsole could not relfect usage of non-heap memory

I use ByteBuffer.allocateDirect(int) to allocate direct buffer(100M) on non-heap space until java.lang.OutOfMemoryError: Direct buffer memory error thrown. But when I use jconsole to monitoring the non-heap memory usage, no direct buffer used memory…
Machi
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Direct buffer memory issue in Mule - CloudHub RunTime

im facing issue with java.lang.OutOfMemoryError : Direct buffer memory while running the application in Cloud-Hub. here i'm trying to fetch the data from Oracle DB which has 25K records from Inbound table with 1vCore The error occurred after all the…
Karthik
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DirectBuffer, deallocation

I allocated a direct buffer: ByteBuffer directBuffer = ByteBuffer.allocateDirect(1024); I've read that: Deallocating Direct Buffer Native Memory in Java for JOGL but it doesn't answer directly. To summarize: GC releases a directbuffer when GC…
Gilgamesz
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How do I correctly work with ByteToMessageCodec.encode and direct buffers

I use a ByteToMessageCodec in my netty project. The encode has the following structure: protected abstract void encode( ChannelHandlerContext ctx, I msg, ByteBuf out ) throws Exception In my case the msg is a message that holds a…
Richard Burkhardt
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Direct frame buffer access using OpenCL and SWT

I've written an OpenCL-kernel (JOCL) which takes a few hundred megabytes of input data and produces a viewport-friendly RGB-Image as result. This image shall be presented in an SWT-GUI with a refresh rate of about at least 10 fps to allow realtime…
Kai Giebeler
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