Questions tagged [dma]
The dma tag has no usage guidance.
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SMART: UltraDMA selected jumps back and forth between 5 and 6
Every time I am viewing SMART-Data of my SATA SSD (Samsung 870 EVO 2TB) with Disk Checkup software I see different value of "UltraDMA selected" parameter. It is times 5 times 6. May be it ...
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How does direct memory access improve performance
A wikipedia article about DMA says that the cpu has to be put in a hold state to prevent bus contention since peripherals and cpu share the memory bus, but if the main way dma mechanism improves ...
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Is this DMA protection in Group Policy different from Kernel DMA protection?
There is a Bitlocker DMA protection and then there is Kernel DMA protection. the latter is better and enabled by default on capable hardware, the former is only suggested to be used when hardware ...
user1752038
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How is I/O encryption handled in modern systems? [closed]
First: I've struggled with the question on which stackexchange to post this question since it involves OS knowledge, hardware knowledge but probably also other CS fields. Suggestions for a better ...
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Force process to always be in RAM on Windows
I would like the process I'm using, to never be in the Windows page file. This isn't for performance, rather I wish to use DMA to monitor it. If the used virtual address space isn't in RAM I can't ...
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What limits how much of the memory a PCIe device can address?
Some PCIe devices cannot read more than 4 GB of address space without an additional driver or modified driver. In such cases, what limits how much memory they can read? Is it the memory controller? Is ...
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My Mouse lags on HDD Activity after Ubuntu 19.10 Upgrade
I have recently upgraded from Ubuntu 19.04 to Ubuntu 19.10. But after upgrade I noticed that my mouse starts lagging while doing file transfers or any hard drive activity.
Can anyone explain why is ...
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What Instructions does a CPU give to DMA?
I understood on a very high level that CPU instructs DMA to fetch data from Hard Disk and load it in RAM.
Even though I am a .Net Developer and I don't need any of this in my daily job but still I ...
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Extending the kernel's 4MB limit for memory allocations using DMA api - dma_alloc_coherent
I'm using Ubuntu 16.04, and I'd like to use dma_alloc_coherent to allocate a DMA buffer (non-cached) that is larger than 4MB. When I attempt to do this, the call returns a NULL. I've tried the kernel ...
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Un-allowed DMA capable bus/device(s) detected
My problem is how can I find out which device on my laptop is Un-allowed DMA capable. I tried disabling my USB devices and unplugging laptop from docking station. My colleague has same laptop model ...
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I can't change SATA hard disk (working in UDMA) to PIO mode in Linux
I'm trying to disable DMA in my SATA 3.5" hard disk drive to work in PIO mode because for recovering some bad sectors from a failing disk with GNU ddrescue
I am using PartedMagic Linux live CD and I ...
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Size of one DMA block
When DMA is used, the whole block of memory is transferred from I/O device to main memory.
I am interested in the size of this block, more specifically in the answers to these questions:
Is the size ...
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Location of Windows video memory
I'm currently analyzing a KVM solution. For this purpose I would like to locate the Windows video memory which is used by the KVM probably using DMA. Is there a way to achieve this?
The system is ...
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How to implementing a application with Linux DMA
As far as I know, Linux provides common DMA framework for various DMA engine and a device driver for DMA engine have to be implemented based on the the framework.
Is the framework provide any system ...
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Monitoring DMA Performance in Windows?
Why DMA is not listed in windows performance monitor's available counters? RDMA Activity is already present but not DMA. Is it possible to monitor DMA in windows?
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