From 571a5da50fc660ffd78d25633eee414c40d1cdc1 Mon Sep 17 00:00:00 2001 From: Geoffrey McRae Date: Sun, 18 Sep 2022 12:12:49 +1000 Subject: [PATCH] [doc] add requirements page --- doc/index.rst | 1 + doc/requirements.rst | 82 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 83 insertions(+) create mode 100644 doc/requirements.rst diff --git a/doc/index.rst b/doc/index.rst index 35ffb0de..b46e8286 100644 --- a/doc/index.rst +++ b/doc/index.rst @@ -10,6 +10,7 @@ systems for legacy programs that require high-performance graphics. .. toctree:: :maxdepth: 2 + requirements usage install build diff --git a/doc/requirements.rst b/doc/requirements.rst new file mode 100644 index 00000000..e1987d2c --- /dev/null +++ b/doc/requirements.rst @@ -0,0 +1,82 @@ +.. _requrements: + +Requirements +############ + +.. _minimum_: + +Minimum +------- + +The most basic requirement to make use of Looking Glass is to have a system +with two GPUs, the following configurations are valid: + +* Two descrete GPUs (dGPU) +* A descrete GPU and an integrated (iGPU) such as is common in laptops. +* A descrete GPU or iGPU and a virtual GPU (vGPU) as supported by some + hardware. + +.. note:: + Please be aware that iGPU users may be limited in the resolution and refresh + rate possible with Looking Glass due to the memory bandwidth limitations + imposed due to the iGPU sharing system RAM for GPU usage. + +Looking Glass aims to achieve the lowest possible latency and as such it +is important that you do not overload your system. The minimum recommended CPU +to obtain a decent expereience with Looking Glass is 6 cores or more, with +Hyper-threading (>= 12 threads). + +PCIe bandwidth can also be a limiting factor, as such both GPUs should have a +minimum of 8 lanes (x8) at PCIe3 speeds, or 4 lanes (x4) at PCIe4 speeds. + +The GPU used for the guest virtual machine must have either a physical monitor +attached to it, or a cheap dummy plug. The guest operating system (most notibly +Windows) will disable the GPU output if there is nothing attached to it and +Looking Glass will not be able to function. If you are using a vGPU the virtual +device should already have a virtual monitor attached to it negating this +requirement. + +.. _recommended_: + +Recommended +----------- + +At this time the recommended configuration is as follows: + +* CPU 8 cores (16 threads) or better @ 3.0GHz or faster (full cores, not + efficiency cores). + +* Two descrete GPUs consisting of: + + * AMD or Intel brand GPU for the client application (usually your host system). + * NVIDIA brand GPU for the guest system (virtual machine). + +The reason for these reccomendations are as follows: + +AMD or Intel for the client +^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +AMD and Intel both support the `DMABUF` feature which enables offloading memory +transfers to the GPU hardware. Please note that making use of this feature +requires :doc:`loading the KVMFR kernel module `. + +Additionally AMD GPUs suffer stabillity issues when operating as a passthrough +device and as such we do not recommend their usage for such purposes. Models of +note that have issues include but are not limited to the entire Polaris, Vega, +Navi and BigNavi GPU series. Vega and Navi are notibly the worst and should be +avoided for virtualization usage. + +NVIDIA for the guest +^^^^^^^^^^^^^^^^^^^^ + +NVIDIA unlike AMD do not seem to suffer from the same stabillity issues as AMD +GPUs when operating as a passthrough GPU, however due to the closed source +nature of their drivers NVIDIA can not make use of the DMABUF feature in the +Linux kernel and as such it is not recommended for use as the host GPU. + +`It has been said `_ +that the open-source NVIDIA drivers as of release 525 will enable this support +and we have made changes to `an experiemental branch `_ +to support this, however until NVIDIA release this version and we can test these +changes against the driver, support will not be included in the release builds +of Looking Glass.