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Questions tagged [coalescing]

49 questions
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cuda memory coalescing

I would like first to confirm the following: The elementary global memory transaction to shared memory is either 32 bytes, 64 or 128 bytes, but only if the memory accesses can be coalesced. The latencies of the precedent transactions are all…
hristo jancovic
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HLSL: Memory coalescing with structured buffers

I'm currently working on an HLSL shader that is limited by global memory bandwidth. I need to coalesce as much memory as possible in each memory transaction. Based on the guidelines from NVIDIA for CUDA and OpenCL (DirectCompute documentation is…
tiredNconfused
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Fill the NAs values in a dataframe based on calculation of columns in other dataframe

I have 2 dataframes. The RP and the RP2. My goal is to fill the NAs of RP columns Country_1 and Country_2 based on the conditions below: 1.If a cell of RP has already value leave it as it is. 2.If it has NA then see the TreatmenArea and Subarea of…
firmo23
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R Proper use for across() function with na.locf()

I am trying to replicate this SO question, but by using the updated syntax which uses the across() function and gets away from the deprecated summarise_all() and funs(). Starting Data I have a database extract that one row per event type, like…
ScottyJ
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CUDA coalescing and global memory

I have been told in my CUDA course that the following access (global memory) is coalescaled if elements of my "a" array have a size of 4,8 or 16 bytes. int i = blockIdx.x*blockDim.x + threadIdx.x; a[i]; The 2 conditions for coalescing are : …
Jack Dero
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Memory coalescing and nvprof results on NVIDIA Pascal

I am running a memory coalescing experiment on Pascal and getting unexpected nvprof results. I have one kernel that copies 4 GB of floats from one array to another one. nvprof reports confusing numbers for gld_transactions_per_request and…
Matthias Springer
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Swift 4.2 coalescing while downcasting multiple variables in a single if-let

I recently started learning Swift, now I'm trying to safely unwrap multiple variables that come from a JSON response which might contain or not that key. Example of the JSON response: { "products: [{ "foo": "foo" "bar": "bar" …
Frakcool
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Swift nil coalescing operator with array

I am trying out an exercise in creating a simple todo list. Before introducing Realm or coreData i wanted to test it out and see if everyting is going smoothly. I know i probably can make this work with some if conditions but i would love to be able…
emin
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Coalescing while using NSNotificationQueue

I wrote the following code to perform coalescing using NSNotificationQueue.I want to post only one notification even if the event occurs multiple times. - (void) test000AsyncTesting { [NSRunLoop currentRunLoop]; [[NSNotificationCenter…
user572555
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Is coalesced memory access a feature or phenomenon?

I'm current writing a smaller project in OpenCL, and I'm trying to find out what really causes memory coalescing. Every book on GPGPU programming says it's how GPGPUs should be programmed, but not why the hardware would prefer this. So is it some…
Mads Y
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Xerces XML Document Builder doesn’t coalesce CDATA

After upgrading from Java1.2 and Apache Xerces DomParser to Java1.7 and Xerces JAXP DocumentBuilder, the upgraded parsing completes without errors but does not “unwrap” CDATA elements, despite initializing the DocumentBuilderFactory with…
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Timer Coalescing before Windows 7

There is timer coalescing support in Windows 7 and Windows 8, see for example this: Timer coalescing in .net Windows 7 has a function SetWaitableTimerEx about which it is claimed that it supports coalescing here and here. Windows 8 has additionally…
Roland Pihlakas
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Is incomplete global memory access coalesced?

Is it coalesced, if n < warpSize? // In kernel int x; if (threadId < n) x = globalMem[threadId]; Such situation appers in the last iteration of the cycle, if some N is indivisible by warpSize. Should I run about these sitatuations and alloc…
Nexen
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CUDA pinned memory and coalescing

On a compute capability 2.x device how would I make sure that the gpu uses coalesced memory access when using mapped pinned memory and assuming that normally when using global memory the 2D data would require padding? I can't seem to find…
Aktaeon
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Linux select() and FIFO ordering of multiple sockets?

Is there any way for the Linux select() call relay event ordering? A description of what I'm seeing: On one machine, I wrote a simple program which sends three multicast packets, one to each of three different multicast groups. These packets are…
Matt
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